IFRS 9 loan loss provisioning faces its first real test

My long held view has been that IFSR 9 adds to the procyclicality of the banking system (see here, here, and here) and that the answer to this aspect of procyclicality lies in the way that capital buffers interact with loan loss provisioning (here, here, and here).

So it was interesting to see an article in the Financial Times overnight headlined “New accounting rules pose threat to banks amid virus outbreak”. The headline may be a bit dramatic but it does draw attention to the IFRS 9 problem I have been concerned with for some time.

The article notes signs of a backlash against the accounting rules with the Association of German Banks lobbying for a “more flexible handling” of risk provisions under IFRS 9 and warning that the accounting requirements could “massively amplify” the impact of the crisis. I agree that the potential exists to amplify the crisis but also side with an unnamed “European banking executive” quoted in the article saying “IFRS 9, I hate it as a rule, but relaxing accounting standards in a crisis just doesn’t look right”.

There may be some scope for flexibility in the application of the accounting standards (not my area of expertise) but that looks to me like a dangerous and slippery path to tread. The better option is for flexibility in the capital requirements, capital buffers in particular. What we are experiencing is exactly the kind of adverse scenario that capital buffers are intended to absorb and so we should expect them to decline as loan loss provisions increase and revenue declines. More importantly we should be seeing this as a sign that the extra capital put in place post the GFC is performing its assigned task and not a sign, in and of itself, indicating distress.

This experience will also hopefully reinforce the case for ensuring that the default position is that the Counter Cyclical Capital Buffer be in place well before there are any signs that it might be required. APRA announced that it was looking at this policy in an announcement in December 2019 but sadly has not had the opportunity to fully explore the policy initiative and implement it.

Tony

Capital Rules Get Less Stressful – Matt Levine

Nice quote from Matt Levine’s opinion piece on the change in US bank capital requirements

Everything in bank capital is controversial so this is controversial. Usually the controversy is that some people want higher capital requirements and other people want lower capital requirements. Here, pleasantly, part of the controversy is about whether this is a higher or lower capital requirement.

https://www.bloomberg.com/opinion/articles/2020-03-05/capital-rules-get-less-stressful

Confusing capital and liquidity

I have been planning to write something on the relationship between capital and liquidity for a while. I have postponed however because the topic is complex and not especially well understood and I did not want to contribute to the body of misconceptions surrounding the topic. An article in the APRA Insight publications (2020 Issue One) has prompted me to have a go.

Capital Explained

The article published in APRA’s Insight publication under the title “Capital explained” offers a simple introduction to the question what capital is starting with the observation that …

“Capital is an abstract concept and has different meanings in different contexts.

Capital being abstract and meaning different things in different contexts is a good start but the next sentence troubles me.

“In non-technical contexts, capital is often described as an amount of cash or assets held by a company, or an amount available to invest.”

I am not sure that the author intended to endorse this non-technical description but it was not clear and I don’t think it should be left unchallenged, especially when the casual reader might be inclined to take it at face value. The fact that non-technical descriptions frequently state this is arguably a true statement but the article does not clarify that this description is a source of much confusion and seems to be conflating capital and liquid assets.

The source of the confusion possibly lies in double entry bookkeeping based explanations in which a capital raising will be associated with an influx of cash onto a company balance sheet. What happens next though is that the company has to decide what to do with the cash, it is extremely unlikely that the cash just sits in the company bank account. This is especially true in the case of a bank which has cash flowing into, and out of, the balance sheet every day. The influx of one source of funding (in this case equity) for the bank means that it will most likely choose to not raise some alternate form of funding (debt) on that day. The amount of cash it holds will be primarily driven by the liquidity targets it has set which are related to but in no way the same thing as its capital targets.

Time for me to put up or shut up.

How should we think about the relationship between capital and liquidity including the extent to which holding more liquid assets might, as is sometimes claimed, justify holding less capital.

  • Liquidity risk is mitigated by liquidity management, including holding liquid assets, but this statement offers no insight into the extent to which some residual expected or unexpected aspect of the risk still requires capital coverage (All risks are mitigated to varying extents by management but most still require some level of capital coverage)
  • So the assessment that holding more liquid assets reduces the need to hold capital is open to challenge
  • One of the core functions of capital is to absorb any increase in expenses, liabilities, loan losses or asset write downs associated with or required to resolve an underlying risk issue; the bank may need to recapitalise itself to restore the target level of solvency required to address future issues but the immediate problems are resolved without the consumption of capital compromising solvency
  • Liquid assets, in contrast, buy time to resolve problems but they do not in themselves solve any underlying issues that may be the root cause of the liquidity stress.
  • The relationship between liquidity and solvency is not symmetrical; liquidity is ultimately contingent on a bank being solvent, but a solvent bank can be illiquid.
  • While more liquid assets are not a substitute for holding capital, a more strongly capitalised bank is less likely to be subject to the kinds of liquidity stress events that draw on liquid assets so holding more capital relative to peer banks can reduce liquidity risk
  • Being relatively strong matters in scenarios where uncertainty is high and people resort to simple rules (e.g. withdraw funding from the weakest banks; even if that is not true the risk is that other people express that view and it becomes self-fulfilling)
  • It is important to recognise that the focus of relationship between capital and liquidity risk described above is the capital position relative to peer banks and market expectations, not the absolute stand-alone position
  • The “Unquestionably Strong” benchmark used in the Australian banking system to calibrate the overall target operating range for capital in the ICAAP anchors the bank’s Liquidity Risk appetite setting.
  • Expressed another way, the capital requirements of Liquidity Risk are embedded holistically in the capital buffer the target operating range maintains over prudential minimum capital requirements.

It is entirely possible that I am missing something here – I hope not but let me know if you see an error in my logic

Using machine learning to predict bank distress

Interesting post on the Bank Underground blog by Bank of England staff Joel Suss and Henry Treitel.

This extract summarises their findings

“Our paper makes important contributions, not least of which is practical: bank supervisors can utilise our findings to anticipate firm weaknesses and take appropriate mitigating action ahead of time.

However, the job is not done. For one, we are missing important data which is relevant for anticipating distress. For example, we haven’t included anything that speaks directly to the quality of a firm’s management and governance, nor have we included any information on organisational culture.

Moreover, our period of study only covers 2006 to 2012 – a notoriously rocky time in the banking sector. A wider swathe of data, including both good times and bad, would help us be more confident that our models will perform well in the future.

So while prediction, especially about the future, remains tough, our research demonstrates the ability and improved clarity of machine learning methodologies. Bank supervisors, armed with high-performing and transparent predictive models, are likely to be better prepared to step-in and take action to ensure the safety and soundness of the financial system.”

Possible pitfalls of a 1-in-X approach to financial stability – Bank Underground

Bank Underground is a blog for Bank of England staff to share views that challenge – or support – prevailing policy orthodoxies. The views expressed are those of the authors, and are not necessarily those of the Bank of England, or its policy committees. Posting on this blog, Adam Brinley Codd and Andrew Gimber argue that false confidence in people’s ability to calculate probabilities of rare events might end up worsening the crises regulators are trying to prevent.

The post concludes with their personal observations about how best to deal with this meta-uncertainty.

Policymakers could avoid talking about probabilities altogether. Instead of a 1-in-X event, the Bank of England’s Annual Cyclical Scenario is described as a “coherent ‘tail risk’ scenario”.

Policymakers could avoid some of the cognitive biases that afflict people’s thinking about low-probability events, by rephrasing low-probability events in terms of less extreme numbers. A “100-year” flood has a 1% chance of happening in any given year, but anyone who lives into their 70s is more likely than not to see one in their lifetime.

Policymakers could  be vocal about the fact that there are worse outcomes beyond the 1-in-X point of the distribution.

— Read on bankunderground.co.uk/2020/02/06/possible-pitfalls-of-a-1-in-x-approach-to-financial-stability/

Capital geeks take note – the IRB scaling factor strikes again

Capital

Another reminder on the importance of paying attention to the detail courtesy of a story that I picked up reading Matt Levine’s “Money Stuff” column on Bloomberg.

This extract from Matt’s column captures the essential facts:

Here, from Johannes Borgen, is a great little story about bank capital. Yesterday Coventry Building Society, a U.K. bank, announced “a correction to its calculation of risk weighted assets” that will lower its common equity Tier 1 capital ratio from 34.2% to 32.6%. That’s still well over regulatory requirements, so this is not a big deal. But the way Coventry messed up is funny:

“The Society uses Internal Ratings Based (“IRB”) models to calculate its Risk Weighted Assets (“RWAs”) and is seeking to update these models to ensure compliance with upcoming Basel III  reforms. During the process of transitioning models, the Society has identified an omission in connection with its historic calculation of its RWAs. Specifically, the necessary 6% scalar was not applied to the core IRB model outputs. The core IRB models themselves are not impacted.”

For banks that use Internal Ratings Based models, the way the Basel capital rules work is that you apply a complicated formula to calculate the risk weights of your assets, and then at the end of the formula you multiply everything by 1.06. That’s kind of weird. (The Basel capital regime for banks using IRB models “applies a scaling factor in order to broadly maintain the aggregate level of minimum capital requirements, while also providing incentives to adopt the more advanced risk-sensitive approaches.”) It’s weird enough that in the “upcoming Basel III reforms” regulators plan to get rid of it: The 1.06 multiplier is a kludge, and if you measure your risk-weighted assets a bit more accurately and conservatively, you shouldn’t have to multiply them by 1.06 at the end. 

Matt Levine, “Money Stuff”, Bloomberg

For anyone new to this game who wants to dig a bit deeper into how the advanced capital requirements are calculated, the Explanatory Note published by the BCBS in July 2005 is still a good place to start. I published a note on that paper on my blog here. The RBNZ also produced a useful note on how they used the IRB function in the portfolio modelling work they used to support their recent changes to NZ capital requirements.

It should be noted however that none of these documents discuss the 6% scaling factor. I open to alternative perspectives on this but my recollection is that the 6% scaling factor was introduced post July 2005 in one of the multiple recalibration exercises the BCBS employed to ensure that the IRB function did not reduce capital requirements too much relative to the status quo operating under Basel I. It is effectively a “fudge” factor designed to produce a number the BCBS was comfortable with (at that time).

Tony

APRA announces that it will consider a non-zero default level for the counter cyclical capital buffer

The Australian Prudential Regulation Authority (APRA) announced today that it had decided to keep the countercyclical capital buffer (CCyB) for authorised deposit-taking institutions (ADIs) on hold at zero per cent. What was really interesting however is that the information paper also flagged the likelihood of a non-zero default level in the future.

Here is the relevant extract from the APRA media release:

…. the information paper notes that APRA is also giving consideration to introducing a non-zero default level for the CCyB as part of its broader reforms to the ADI capital framework.

APRA Chair Wayne Byres said: “Given current conditions, and the financial strength built up within the banking sector, a zero counter-cyclical buffer remains appropriate.

“However, setting the countercyclical capital buffer’s default position at a non-zero level as part of the ‘unquestionably strong’ framework would not only preserve the resilience of the banking sector, but also provide more flexibility to adjust the buffer in response to material changes in financial stability risks. This is something APRA will consult on as part of the next stage of the capital reforms currently underway.

“Importantly, this would be considered within the capital targets previously announced – it does not reflect any intention to further raise minimum capital requirements.”

“APRA flags setting the countercyclical capital buffer at non-zero level”, APRA media announcement, 11 December 2019

I have argued the case for a non-zero default setting on this buffer in a long form note I published on my blog here, and published some shorter posts on the countercyclical capital buffer here, here and here). One important caveat is is that incorporating a non-zero default for the CCyB does not necessarily means that a bank needs to hold more capital. It is likely to be sufficient to simply partition a set amount of the existing capital surplus. In this regard, it is interesting that APRA has explicitly linked this potential change to the review it it initiated in the August 2018 Discussion Paper on “Improving the transparency, comparability and flexibility of the ADI capital framework”.

I covered that discussion paper in some depth here but one of the options discussed in this paper (“Capital ratio adjustments”) involves APRA modifying the calculation of regulatory capital ratios to utilise more internationally harmonised definitions of capital and Risk Weighted Assets.

Summing up, I would rate this as a positive development but we need to watch how the policy development process plays out.

Tony

Mortgage Risk Weights – revisited

I post on a range of topics in banking but residential mortgage risk weights is one that seems to generate the most attention. I first posted on the topic back in Sep 2018 and have revisited the topic a few times (Dec 2018, June 2019#1, June 2019#2, and Nov 2019) .

The posts have tended to generate a reasonable number of views but limited direct engagement with the arguments I have advanced. Persistence pays off however because the last post did get some specific and very useful feedback on the points I had raised to argue that the difference in capital requirements between IRB and Standardised Banks was not as big as it was claimed to be.

My posts were a response to the discussion of this topic I observed in the financial press which just focussed on the nominal difference in the risk weights (i.e. 25% versus 39%) without any of the qualifications. I identified 5 problems with the simplistic comparison cited in the popular press and by some regulators:

  • Problem 1 – Capital adequacy ratios differ
  • Problem 2 – You have to include capital deductions
  • Problem 3 – The standardised risk weights for residential mortgages seems set to change
  • Problem 4 – The risk of a mortgage depends on the portfolio not the individual loan
  • Problem 5 – You have to include the capital required for Interest Rate Risk in the Banking Book

With the benefit of hindsight and the feedback I have received, I would concede that I have probably paid insufficient attention to the disparity between risk weights (RW) at the higher quality end of the mortgage risk spectrum. IRB banks can be seen to writing a substantial share of their loan book at very low RWs (circa 6%) whereas the best case scenario for standardised banks is a 20% RW. The IRB banks are constrained by the requirement that their average RW should be at least 25% and I thought that this RW Floor was sufficient to just focus on the comparison of average RW. I also thought that the revisions to the standardised approach that introduced the 20% RW might make more of a difference. Now I am not so sure. I need to do a bit more work to resolve the question so for the moment I just want to go on record with this being an issue that needs more thought than I have given it to date.

Regarding the other 4 issues that I identified in my first post, I stand by them for the most part. That does not mean I am right of course but I will briefly recap on my arguments, some of the push back that I have received and areas where we may have to just agree to disagree.

Target capital adequacy ratios differ materially. The big IRB banks are targeting CET1 ratios based on the 10.5% Unquestionably Strong Benchmark and will typically have a bit of a buffer over that threshold. Smaller banks like Bendigo and Suncorp appear to operate with much lower CET1 targets (8.5 to 9.0%). This does not completely offset the nominal RW difference (25 versus 39%) but it is material (circa 20% difference) in my opinion so it seem fair to me that the discussion include this fact. I have to say that not all of my correspondents accepted this argument so it seems that we will have to agree to disagree.

You have to include capital deductions. In particular, the IRB banks are required to hold CET1 capital for the shortfall between their loan loss provision and a regulatory capital value called “Regulatory Expected Loss”. There did not appear to be a great awareness of this requirement and a tendency to dismiss it but my understanding is that it can increase the effective capital requirement by 10-12% which corresponds to an effective IRB RW closer to 28% than 25%.

The risk of a mortgage depends on the overall portfolio not the individual loan. My point here has been that small banks will typically be less diversified than big banks and so that justifies a difference in the capital requirements. I have come to recognise that the difference in portfolio risk may be accentuated to the extent that capital requirements applied to standardised banks impede their ability to capture a fair share of the higher quality end of the residential mortgage book. So I think my core point stands but there is more work to do here to fully understand this aspect of the residential mortgage capital requirements. In particular, I would love get more insight into how APRA thought about this issue when it was calibrating the IRB and standardised capital requirements. If they have spelled out their position somewhere, I have not been able to locate it.

You have to include the capital required for Interest Rate Risk in the Banking Book (IRRBB). I did not attempt to quantify how significant this was but simply argued that it was a requirement that IRB banks faced that standardised banks did not and hence it did reduce the benefit of lower RW. The push back I received was that the IRRBB capital requirement was solely a function of IRB banks “punting” their capital and hence completely unrelated to their residential mortgage loans. I doubt that I will resolve this question here and I do concede that the way in which banks choose to invest their capital has an impact on the size of the IRRBB capital requirement. That said, a bank has to hold capital to underwrite the risk in its residential mortgage book and, all other thinks being equal, an IRB bank has to hold more capital for the IRRBB requirement flowing from the capital that it invests on behalf of the residential mortgage book. So it still seems intuitively reasonable to me to make the connection. Other people clearly disagree so we may have to agree to disagree on this aspect.

Summing up, I had never intended to say that there was no difference in capital requirements. My point was simply that the difference is not as big as is claimed and I was yet to see any analysis that considered all of the issues relevant to properly understand what the net difference in capital requirements is. The issue of how to achieve a more level playing field between IRB and Standardised Banks is of course about much more than differences in capital requirements but it is an important question and one that should be based on a firmer set of facts that a simplistic comparison of the 39% standardised versus 25% IRB RW that is regularly thrown around in the discussion of this question.

I hope I have given a fair representation here of the counter arguments people have raised against my original thesis but apologies in advance if I have not. My understanding of the issues has definitely been improved by the challenges posted on the blog so thanks to everyone who took the time to engage.

Tony

Australian banking – “Unquestionably Strong” gets a bit more complicated

Students of the dark art of bank capital adequacy measurement were excited this week by the release of some proposed revisions to APRA’s “Prudential Standard APS 111 Capital Adequacy” (APS 111); i.e. the one which sets out the detailed criteria for measuring an ADI’s Regulatory Capital.

Is anyone still reading? Possibly not, but there is something I think worth noting here if you want to understand what may be happening with Australian bank capital. This is of course only a consultation at this stage but I would be very surprised if the key proposal discussed below is not adopted.

The Short Version

The consultation paper has a number of changes but the one that I want to focus on is the proposal to apply stricter constraints on the amount of equity an ADI invests in banking and insurance subsidiaries.

In order to understand how this impacts the banks, I have to throw in two more pieces of Australian bank capital jargon, specifically Level 1 and Level 2 capital.

  • Level 1 is the ADI itself on a stand alone basis (note that is a simplification but close enough to the truth for the purposes of this post).
  • Level 2 is defined in the consultation paper as “The consolidation of the ADI and all its subsidiaries other than non-consolidated subsidiaries; or if the ADI is a subsidiary of a non-operating holding company (NOHC), the consolidation of the immediate parent NOHC and all the immediate parent NOHC’s subsidiaries (including any ADIs and their subsidiaries) other than non-consolidated subsidiaries.”

You can be forgiven for not being familiar with this distinction but the capital ratios typically quoted in any discussion of Australian bank capital strength are the Level 2 measures. The Unquestionably Strong benchmark that dominates the discussion is a Level 2 measure. The changes proposed in this consultation however operate at the Level 1 measurement (the ones that virtually no one currently pays any attention to) and not the Level 2 headline rate.

This has the potential to impact the “Unquestionably Strong” benchmark and I don’t recollect seeing this covered in the consultation paper or any public commentary on the proposal that I have seen to date.

APRA has been quite open about the extent to which these changes are a response to the RBNZ proposal to substantially increase equity requirements for NZ banks.

“This review was prompted in part by recent proposals by the Reserve Bank of New Zealand (RBNZ) to materially increase capital requirements in New Zealand. The RBNZ’s proposals and APRA’s processes are a natural by-product of both regulators working to protect their respective communities from the costs of financial instability and the regulators continue to support each other as these reforms are developed.”

The changes have however been calibrated to maintain the status quo based on the amounts of capital the Australian majors currently have invested in their NZ subsidiaries.

“APRA has calibrated the proposed capital requirements so they are broadly consistent with … the current capital position of the four major Australian banks, in respect of these exposures (i.e. preserving most of the existing capital uplift).”

It follows that any material increase in the capital the majors are required to invest in their NZ subsidiaries (in response to the RBNZ’s proposed requirement) will in turn require that they have to hold commensurately more common equity on a 1:1 basis in the Level 1 ADI to maintain the existing Level 1 capital ratios.

So far as I can see, the Level 2 measure does not require that this extra capital invested in banking subsidiaries be subject to the increased CET1 deductions applied at Level 1. It follows that the Level 2 CET1 ratio will increase but the extent to which a creditor benefits from that added strength will depend on which part of the banking group they sit.

I am not saying this a problem in itself. The RBNZ has the authority to set the capital requirements it deems necessary, Australian bank shareholders can make their own commercial decisions on whether the diluted return on equity meets their requirements and APRA has to respond to protect the interests of the Australian banking system.

I am saying that measuring relative capital adequacy is getting more complicated so you need to pay attention to the detail if this matters to you. In particular, I am drawing attention to the potential for the Level 2 CET1 ratios of the Australian majors to increase in ways that the existing “Unquestionably Strong” benchmark is not calibrated to. I don’t think this matters much for Australian bank depositors who have a very safe super senior position in the Australian loss hierarchy. It probably does matter for creditors who are closer to the sharp end of the loss hierarchy including senior and subordinated bondholders.

To date, the Level 2 capital adequacy ratios have been sufficient to provide a measure of relative capital strength; a higher CET1 ratio equals greater capital strength and that was probably all you needed to know. Going forward, I think you will need to pay closer attention to what is happening at the Level 1 measure to gain a more complete understanding of relative capital strength. The Level 2 measure by itself may not tell you the full story.

The detail

As a rule, APRA’s general capital treatment of equity exposures is to require that they be deducted from CET1 Capital in order to avoid double counting of capital. The existing rules (APS 111) however provides a long-standing variation to this general rule when measuring Level 1 capital adequacy. This variation allows an ADI at Level 1 to risk weight (after first deducting any intangibles component) its equity investments in banking and insurance subsidiaries. The risk weight is 300 percent if the subsidiary is listed or 400 per cent if it is unlisted.

APRA recognises that this improves the L1 ratios by around 100bp versus what would be the case if a full CET1 deduction were applied but is comfortable with that outcome based on current exposure levels.

The RBNZ’s (near certain) move towards higher CET1 requirements however threatens to undermine this status quo and potentially see a greater share of the overall pool of equity in the group migrate from Australia to NZ. APRA recognises of course that the RBNZ can do whatever it deems best for NZ depositors but APRA equally has to ensure that the NZ benefits do not come at the expense of Australian depositors (and other creditors).

To address this issue, APRA is proposing to limit the extent to which an ADI may use debt to fund investments in banking and insurance subsidiaries.

  • ADIs, at Level 1, will be required to deduct these equity investments from CET1 Capital, but only to the extent the investment in the subsidiary is in excess of 10 per cent of CET1 Capital.
  • An ADI may risk weight the investment, after deduction of any intangibles component, at 250 per cent to the extent the investment is below this 10 per cent threshold.
  • The amount of the exposure that is risk weighted would be included as part of the related party limits detailed in the recently finalised APS 222.

As APRA is more concerned about large concentrated exposures, it is proposing to limit the amount of the exposure to an individual subsidiary that can be leveraged to 10 per cent of an ADI’s CET1 Capital. This means capital requirements are increasing for large concentrated exposures, as amounts over the 10 per cent threshold would be required to be met dollar-for-dollar by the ADI parent company.

Summing up

What APRA is proposing to do makes sense to me. We can debate the necessity for the RBNZ to insist on virtually 100% CET1 capital (for the record, I continue to believe that a mix of CET1 and contingent convertible debt is likely to be a more effective source of market discipline). However, once it became clear that the RBNZ was committed to its revised capital requirements, APRA was I think left with no choice but to respond.

What will be interesting from here is to see whether investments of CET1 in NZ banking subsidiaries increase in response to the RBNZ requirement or whether the Australian majors choose to reduce the size of their NZ operations.

If the former (i.e. the majors are required to increase the capital committed to NZ subsidiaries) then we need to keep an eye on how this impacts the Level 2 capital ratios and what happens to the “Unquestionably Strong” CET1 benchmark that currently anchors the capital the Australian majors maintain.

This is a pretty technical area of bank capital so it is possible I am missing something; if so please let me know what it is. Otherwise keep an eye on how the capital adequacy targets of the Australian majors respond to these developments.

Tony (From the Outside)

Bank funding costs and capital structure – what I missed

A recent post looked at a Bank of England paper that offered evidence that the cost of higher capital requirements will be mitigated by a reduction in leverage risk which translates into lower borrowing costs and a decline in the required return equity. My post set out some reasons why I struggled with this finding.

My argument was that,

  • in banking systems where the senior debt rating of banks assumed to be Too Big To Fail is supported by an implied assumption of government support (such as Australia),
  • increasing the level of subordinated debt could reduce the value of that implied support,
  • however, senior debt itself does not seem to be any less risky (the senior debt rating does not improve), and
  • the subordinated debt should in theory be more risky if it reduces the value of the assumption of government support.

Fortunately, I also qualified my observations with the caveat that it was possible that I was missing something. Recent issuance of Tier 2 debt by some Australian banks offers some more empirical evidence that does seem to suggest that the cost of senior debt can decline in response to the issuance of more junior securities and that the cost of subordinated debt does not seem to be responding in the way that the theory suggests.

My original argument was I think partly correct. The prospect of the large Australian banks substantially increasing the relative share of Tier 2 debt in their liability structure has not resulted in any improvement in the AA- senior debt rating of the banks subject to this Total Loss Absorbing Capital requirement. So senior debt does not seem to be any less risky.

What I missed was the impact of the supply demand dynamic in a low interest rate environment where safe assets are in very short supply.

The senior debt in my thesis is no less risky but the debt market appears to be factoring in the fact that the pool of AA- senior debt is likely to shrink relative to what was previously expected. Investors who have been struggling for some time to find relatively safe assets with a decent yield weigh up the options. A decent yield on safe assets like they used to get in the old days would obviously be preferable but that is not on offer so they pay up to get a share of what is on offer.

The subordinated debt issued by these banks might be more risky in theory to the extent that bail-in is now more credible but if you do the analysis and conclude that the bank is well managed and low risk then you discount the risk of being bailed-in and take the yield. Again the ultra low yield on very safe assets and the shortage of better options means that you probably bid strongly to get a share of the yield on offer.

Summing up. The impacts on borrowing costs described here may look the same as what would be expected if the Modigliani-Miller effect was in play but the underlying driver appears to be something else.

It remains possible that I am still missing something but hopefully this post moves me a bit closer to a correct understanding of how capital structure impacts bank funding costs …

Tony