Comparison of the Bloomberg curve with long-dated bonds
82 The AER placed great emphasis on the fact that, in determining the implied fair value yield at ten years using Bloomberg data, an extrapolated curve was being used. That is, the information was not published by Bloomberg as part of the BBB fair value curve. The method of extrapolation was, however, not in contention between the parties.
83 The AER's submissions suggest that, because the EBV is an extrapolation at the 10-year point, greater scrutiny should be applied to its reliability. This is no doubt correct. Allgas agreed with the proposition that it is appropriate for the AER to investigate the reliability of any measure it is using to determine the DRP.
84 The AER's analysis of the reliability of the Bloomberg curve in the Final Decision rested on a comparison of an estimated yield derived from the Bloomberg curve with a sample of long-dated bonds. In particular, the AER relied on the following figure which depicts an extrapolation from 31 May 2018 to 31 May 2021:
Figure 1: Australian corporate bonds with maturities greater than five years and credit ratings from BBB to A- (Final Decision: Figure A.5)
85 What becomes immediately obvious on viewing the AER's preferred depiction of the data is that a significant proportion of the plotted bonds lie beneath the Bloomberg curve and, in particular, below its extrapolated portion. At first blush this may suggest that the Bloomberg curve, at least the extrapolated portion, overstates true yields.
86 The problem with this view, however, is that it ignores the generally held proposition that yield curves slope upwards, a view accepted by both parties. For the Bloomberg curve to accurately reflect the yields displayed by the sample of long-dated bonds preferred by the AER it would be required to slope downward from the point at which extrapolation commences. The required change in direction becomes even more apparent when Allgas's preferred figure is inspected, but ignoring the additional bond sample:
Figure 2: Bloomberg BBB Fair Value Curve extrapolated to 15 years and reported yields (CEG's response to the May 23 letter).
87 The additional bond sample comprises the three bonds labelled "SUNCORP", the bond labelled "DBCT" at the far right of the figure, the two bonds labelled "VERO", the two bonds labelled "BKQLD" and the bond labelled "AMP". These bonds were not included in the AER's preferred figure, being Figure 1 above.
88 Rather than casting doubt on the reliability of the extrapolation, the AER's analysis, if accepted, would cast doubt on the overall reliability of the Bloomberg curve at all, as a reflection of Australian corporate bond yields. Perhaps a more plausible explanation for the apparent incongruity between the Bloomberg curve and the reported yields on the AER's sample of long-dated bonds is that the sample of bonds used by the AER is not complete or representative. The AER's view that the Bloomberg curve overstated relevant bond yields may have been one that was open to it had the only available evidence been the sample it selected. This was not, however, the case.
89 As observed in [71] above, in response to the May 23 letter, Allgas relied on an expert report from CEG (this report is the source of Figure 2 above), which identified additional bonds that, in CEG's analysis, should be included in the comparison sample. The AER claimed that it did not have sufficient time to fully analyse CEG's response to the May 23 letter before publication of the Final Decision.
90 If these additional bonds are included in the sample, the extrapolated Bloomberg curve over the entire 15-year period appears to be much more reliable in terms of being representative of the whole sample of bonds. In particular, several of the new bonds lie substantially above the Bloomberg curve, at periods to maturity greater than 10 years.
91 The new sample of bonds arose, in large part, because Dr Hird, the CEG Report's author, changed the methodology he used to determine the maturity date of callable bonds. Previously he had used the first call date as the appropriate date of maturity. For the later report, Dr Hird instead used the final call, or final maturity, date in circumstances in which the call option is unlikely to be exercised. The AER in submissions through counsel on the review accepted the correctness of this approach, but had several criticisms of the inclusion of these bonds in the sample, at least in their current form.
92 In ActewAGL at [39], the Tribunal said that, when using a sample of bonds to check the reliability of a fair value curve, the sample should be as large as possible. In ActewAGL, the Tribunal was considering the basis on which the AER attempted to decide which of three fair value curves was most representative. In that case, the Tribunal stated that a sample of five bonds was insufficient, particularly when these bonds only covered half of the relevant term to maturity: ActewAGL at [39]. In the present matter the AER used a sample of seven bonds to reach its conclusion in the Final Decision. These bonds were, however, bunched tightly across time. Little consideration was given to the relevance of shorter or longer dated bonds in testing the overall validity of the Bloomberg curve or the representativeness of the APA bond. While it may be accepted that bonds with a maturity of approximately 10 years may be particularly relevant, they should not be considered to the exclusion of all others in deriving a representative estimate of the DRP.
93 The inclusion or otherwise of the additional bonds put forward by the CEG report may be of crucial importance in determining whether the Bloomberg curve provides a reliable estimate of 10 year BBB+ corporate bond yields. It was not an appropriate response by the AER to publish the Final Decision without considering, and if appropriate, taking into account the suggestions made by CEG.
94 For these reasons, a detailed analysis as to whether inclusion of the bonds proposed by CEG should have been undertaken. If, as the AER submits, there are anomalies with the yields used, suitable adjustments might be required to be made. Likewise, any adjustments to remove the value of the call options might also be necessary.
95 In the Final Decision the AER said:
In the limited timeframe available to assess CEG's proposal, the AER has been unable to adequately verify the reasonableness of CEG's changed methodology. Regardless, the AER considers that the additional bonds noted by CEG are immaterial for this final decision.
96 The AER did not therefore investigate or methodically analyse the validity of CEG's proposal. The AER's analysis only extended to noting that bonds issued by financial institutions often have higher yields than those issued by infrastructure service providers and that several of the bonds in CEG's proposed sample were subordinated debt.
97 As Allgas correctly submitted, the nature of the debt, that is subordinated or unsubordinated, and the industry of the issuer should be taken into account in the determination of the bond's credit rating. Similarly, the industry of the issuer is not relevant within the current structure of the AER's process. If the AER is to continue to use BBB+ rated corporate debt as its benchmark for determining the DRP, it is not reasonable for it to pick and choose which of the BBB+ bonds it deems to be appropriate without considering the significance of the other potentially relevant bonds. The analysis of all potentially relevant bonds as assessed by Bloomberg produces the EBV. If the AER were to decide that the EBV was an unreliable indicator for the purposes of deciding that DRP, it would be desirable in the longer term to develop an alternative coherent and consistent methodology, in consultation with the relevant regulated entities and other interested parties. Although the DRP must be determined at a particular point in time, the use of a consistent and acceptable methodology would ensure regulatory consistency, and in relation to particular matters would also facilitate efficient decision making and in turn perhaps reduce the number of reviews of the DRP decisions by the AER brought to the Tribunal. While such a task would be a complex and lengthy one, it is one the Tribunal commends to the AER.
98 However, given the time constraints upon its decision making, that was not an option available to the AER in this matter. It is necessary to determine whether the AER committed reviewable error in the manner of selection of the DRP on the material available to it, and upon which it was obliged to make its decision.
99 Focusing on the industry of the issuer and being selective in choosing which BBB+ rated corporate debt to use for determining the DRP is a novel technique by the AER. This would require a different approach from the AER and different submissions from service providers.
100 Rule 62(1) of the NGR requires the AER to consider all submissions made in response to the Draft Decision before making the Final Decision, as well as any other matters it thinks relevant. While, strictly, the May 23 letter did not form part of the Draft Decision, it was a significant course of action for the AER to propose a substantial variation to its approach from the Draft Decision without giving Allgas much of an opportunity to respond and, having received the response in a timely manner, in the circumstances explained by the AER, fail to give Allgas' response thorough consideration.
101 The Tribunal appreciates the constraints of the timetable to be observed by the AER and the risk that a regulated entity may 'game' the timetable. But here, the timing issue was one of the AER's own making. Indeed, this was an issue that could have been raised and addressed by the AER so that it did have sufficient time to fully analyse CEG's response to the May 23 letter.
102 The AER appears to have reached a hybrid position. It properly decided to review the reliability of the EBV. However, in doing so, it selectively relied on the APA bond. For the reasons given, the Tribunal considers that that was not appropriate. There had been identified to the AER a range of other bonds, some of which lay below the EBV and some above the EBV. Had the AER considered them, its caution about the limited use of the EBV may have been resolved. The hybrid position emerges from the fact that the AER nevertheless decided to rely on the EBV as one of the two significant inputs into its weighting process. It must therefore have regarded the EBV as relevant and meaningful.
103 The AER, having rejected placing sole reliance on the EBV, decided to use the APA bond as a component of an averaging process. After first considering placing a 70% weight on the APA bond it decided to determine the DRP based on an average of the APA bond and the EBV, giving a 50% weight to each.
104 The choice of the APA bond and the weighting applied to it are attended by the same error as the decision to reject the sole use of the EBV, namely the failure to have sufficient regard to the expert report of CEG. As noted, this report was prepared in response to the AER's proposal to place a 70% weight on the APA bond. No consideration appears to have been given to the question of whether the APA bond has been used by the market, broadly defined, as a reference for determining acceptable yields for bonds with similar credit ratings and terms to maturity. Indeed, no consideration has been given to the question of whether it is accepted practice in the market to estimate reference yields on the basis of a single bond. The lack of consideration of this issue runs counter to the emphasis placed on market use of, and reliance on, evaluative techniques in ActewAGL at [78] and reiterated in Jemena (No 5) at [64].
105 The manner in which the weightings in the averaging process were assigned was also in error. As was said in ActewAGL and Jemena (No 5), the process of averaging needs to be given significant consideration and the allocation of weights should be done on a scientific basis. The Tribunal noted, in discussing the processing of averaging two fair value curves in Jemena (No 5) that:
An average is a blunt instrument unless careful thought is given to the individual components and whether each should be given the same consideration, or weight, in the calculation of the average. A simple unweighted average gives each component the same weight. This will not always be appropriate, especially where (as here) the two fair value curves differ considerably over the relevant periods to maturity.
106 This point is apposite in the current matter. There is a substantial difference between the DRP implied by the EBV and that implied by the APA bond. To take a simple average of these, without consideration of the methodology behind the Bloomberg curve, or the relevance of selecting just the APA bond from the whole sample of bonds (including longer and shorter dated bonds) is to use a very heavy "blunt instrument" when a more nuanced, rigorous and sophisticated method is required.
107 The sole basis for the assignment of weights in this matter was the AER's opinion that the APA bond and the EBV (based as it is on the yields of 18 bonds) were each equally reliable as indicators of the benchmark DRP. No explicit consideration appears to have been given to the fact that the APA bond was being used as a quasi-proxy for the other bonds the AER deemed as appropriate comparators, nor is there any consideration given to the nature of the Bloomberg curve, which is derived from a sample of 18 bonds.
108 The placing of equal weight on the APA bond and the EBV estimate effectively assigns a 50% weight to one bond, the APA bond, and a 2.8% weight to each of the 18 bonds comprising the Bloomberg curve sample. The AER has not provided any analysis, or demonstrated any consideration, of whether this division of weights is correct.
109 The choice of weights in the averaging process is of vital importance. It should not be undertaken in an arbitrary or haphazard manner. Any decision on weighting must have a sound and reasoned logic.
110 In the view of the Tribunal, the decision to reject the adoption of the EBV on the basis of the APA bond and the weighting chosen amounts to reviewable error on the part of the AER. The reviewable grounds invoked by Allgas are primarily under s 246(1)(c) and (d), although it also asserts material errors of fact so as to enliven s 246(1)(a) and (b). In the view of the Tribunal, the AER in the circumstances made a decision which was unreasonable by adopting a rate of return for the DRP based upon the simple averaging of the EBV and the APA bond. There may be reasons why some or all of the bonds referred to in Allgas' response to the May 23 letter are inappropriate to be considered. However, the AER regarded those bonds as "immaterial" without sufficient grounds for doing so. Given the common understanding of both Allgas and the AER as to the nature of the bonds considered in the formulation of the Bloomberg curve (that is, before its extrapolation), there was no apparent reason to exclude those bonds because they were issued by financial institutions. That is not how the AER had proceeded in the past, when averaging the EBV and the extrapolated CBA Spectrum value. That step on the part of the AER, in the Tribunal's view, rendered its reviewable decision unreasonable because the consequences of its error were obviously of significant magnitude. The significance of the different approach is addressed in the reasons for decision of the Tribunal giving leave to Allgas to apply to review the AER reviewable decision: Application by APT Allgas Energy Pty Ltd [2011] ACompT 11. It is also an error capable of being expressed within the terms of s 246(1)(c), that is as an incorrect exercise of the AER's discretion in selecting the rate of return for the DRP as it did without considering the increased bond sample proposed by Allgas, particularly as the AER by the 23 May letter invited comment on a variation of the weighting proposed in the Draft Decision.
111 Thus, Allgas has successfully made out a ground of review: NGL s246(1)(c) and (d). Accordingly, the Tribunal must decide whether to vary the AER's decision, affirm the AER's decision or remit the matter back to the AER for further consideration: NGL s 259(2). Before doing so, there are a couple of other matters to be mentioned.