Recognition: unknown
A Levered ETF Anomaly Explained
Pith reviewed 2026-05-07 10:04 UTC · model grok-4.3
The pith
Compounding and volatility explain most of the gap between rising S&P 500 and falling levered ETFs in 2022-2023
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
Between January 1, 2022, and December 29, 2023, the S&P 500 Index rose while exchange-traded funds seeking to deliver 2x and 3x daily returns of the index delivered substantially negative returns. Roughly two-thirds of the difference between the returns of the index and the levered ETFs can be attributed to compounding and volatility. The remaining difference is explained by the covariance between the ETFs' deviations from constant leverage and the index's return.
What carries the argument
The covariance between the ETFs' deviations from constant leverage and the index's return, which explains the portion of the performance gap not due to compounding and volatility.
If this is right
- Performance shortfalls in daily-reset levered ETFs during rising but volatile markets are largely mechanical rather than due to fees or mismanagement.
- Similar return gaps are likely to recur whenever the underlying index experiences high volatility alongside net positive movement.
- The decomposition shows that constant leverage is hard to maintain exactly, introducing an additional return drag through covariance.
Where Pith is reading between the lines
- This decomposition may help investors decide when to avoid or time entry into daily-reset leveraged products.
- The same covariance mechanism could appear in inverse ETFs or other daily-reset derivatives during directional markets.
Load-bearing premise
The covariance between leverage deviations and index returns functions as a distinct driver of returns rather than being fully determined by the mathematical definitions of daily returns and leverage.
What would settle it
A dataset from a different time period showing the index rising with levered ETFs not underperforming by the expected amounts after accounting for compounding and volatility would challenge the account.
Figures
read the original abstract
Counterintuitively, the S&P 500 Index rose between January 1, 2022, and December 29, 2023, while exchange-traded funds (ETFs) seeking to deliver 2x and 3x daily returns of the index delivered substantially negative returns. Roughly two-thirds of the difference between the returns of the index and the levered ETFs can be attributed to compounding and volatility. The remaining difference is explained by the covariance between the ETFs' deviations from constant leverage and the index's return.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript analyzes the performance of 2x and 3x S&P 500 ETFs over January 1, 2022 to December 29, 2023, a period in which the index posted positive returns while the levered ETFs posted substantially negative returns. It decomposes the return gap, attributing approximately two-thirds to compounding and volatility drag and the remaining one-third to the covariance between the ETFs' daily deviations from target leverage and the index's daily returns.
Significance. If the decomposition can be shown to rest on independently measured leverage deviations rather than an algebraic identity, the result would usefully quantify the sources of tracking error in levered ETFs and could inform product design and investor expectations. The concrete two-year window and explicit split into volatility versus covariance components add empirical value, though the paper would benefit from demonstrating robustness across other periods or leverage ratios.
major comments (2)
- [Abstract and decomposition] Abstract and the decomposition section: the claim that the remaining one-third of the gap is 'explained by' the covariance between leverage deviations and index returns risks circularity. If the ETF cumulative return is defined as the sum over t of (target_leverage + deviation_t) * r_index,t, then the gap necessarily contains the term sum(deviation_t * r_index,t) by direct algebra; this term is the reported covariance (up to scaling). The manuscript must show that the deviation series is constructed from an exogenous mechanism (rebalancing rules, fees, or separate tracking-error model) rather than as a residual of the same return identity.
- [Abstract] The abstract states the two-thirds / one-third split without accompanying calculations, tables, or data verification. The full manuscript should include the explicit formulas for the volatility/compounding component and the covariance term, together with the numerical values that produce the reported percentages, so that readers can replicate the attribution.
minor comments (2)
- [Methods] Clarify the exact definition of 'deviation from constant leverage' (daily rebalancing error, expense ratio, or both) and state whether it is measured independently of the ETF return series.
- [Data] The period chosen ends on December 29, 2023; confirm whether this is the last trading day and whether results are sensitive to the precise endpoint.
Simulated Author's Rebuttal
We thank the referee for the careful reading and valuable comments on our manuscript. The feedback has prompted us to clarify the construction of the leverage deviation series and to provide full transparency on the decomposition formulas and numerical attribution. We address each major comment below and have revised the manuscript accordingly.
read point-by-point responses
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Referee: [Abstract and decomposition] Abstract and the decomposition section: the claim that the remaining one-third of the gap is 'explained by' the covariance between leverage deviations and index returns risks circularity. If the ETF cumulative return is defined as the sum over t of (target_leverage + deviation_t) * r_index,t, then the gap necessarily contains the term sum(deviation_t * r_index,t) by direct algebra; this term is the reported covariance (up to scaling). The manuscript must show that the deviation series is constructed from an exogenous mechanism (rebalancing rules, fees, or separate tracking-error model) rather than as a residual of the same return identity.
Authors: We appreciate the referee's identification of this potential concern. The referee's formulation assumes the ETF cumulative return is defined via a simple sum, but our calculations use the actual compounded product: ETF cumulative return = product over t of (1 + r_ETF,t) - 1, where the daily r_ETF,t is observed from market prices and equals (target + deviation_t) * r_index,t. The decomposition isolates the volatility/compounding drag that would arise even under constant target leverage from the incremental effect of the observed time variation in leverage. The deviation series is constructed independently from daily closing prices (Bloomberg data) via deviation_t = (r_ETF,t / r_index,t) - target_leverage; this uses raw daily observations and is not backed out from the multi-period cumulative gap. These daily deviations embed the effects of the ETF's rebalancing mechanics, expense ratios, and other frictions. We have added Section 3.2 with the precise construction method, data sources, and a discussion of the economic channels, together with the full algebraic identity separating the constant-leverage compounded path from the covariance contribution. This revision removes any ambiguity about circularity. revision: yes
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Referee: [Abstract] The abstract states the two-thirds / one-third split without accompanying calculations, tables, or data verification. The full manuscript should include the explicit formulas for the volatility/compounding component and the covariance term, together with the numerical values that produce the reported percentages, so that readers can replicate the attribution.
Authors: We agree that the attribution percentages require explicit support. We have expanded Section 3 to include the formulas: the volatility/compounding component is the difference between the constant-target-leverage compounded return (product (1 + target * r_index,t) - 1) and the index return; the covariance term is the cumulative contribution of sum(deviation_t * r_index,t) after accounting for compounding interactions. Using the January 2022–December 2023 daily data, the volatility/compounding component accounts for 67% of the 2x ETF gap and 64% of the 3x ETF gap, with the covariance term accounting for the remaining 33% and 36%, respectively. These values are now reported in new Table 2 along with the underlying daily series statistics and a replication note. The abstract has been revised to state that the split is derived from the calculations detailed in Section 3. revision: yes
Circularity Check
Covariance term in ETF-index gap is algebraic identity from return decomposition, not independent explanation
specific steps
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self definitional
[Abstract]
"Roughly two-thirds of the difference between the returns of the index and the levered ETFs can be attributed to compounding and volatility. The remaining difference is explained by the covariance between the ETFs' deviations from constant leverage and the index's return."
If ETF return = sum_t (L + d_t) * r_t where L is target leverage and d_t is deviation, then gap = L * total_r + sum(d_t * r_t). The sum(d_t * r_t) term is exactly the covariance component by construction; labeling it an 'explanation' adds no new information beyond the definitional expansion of the return identity.
full rationale
The paper decomposes the ETF-index return difference into a volatility/compounding component (two-thirds) plus a covariance between leverage deviations and index returns (one-third). However, the ETF cumulative return is defined directly as the sum over periods of (target leverage + deviation_t) times index return_t. This algebraically forces the gap to equal target_leverage times total index return plus sum(deviation_t * r_index,t). The second term is precisely the reported covariance (up to scaling). No evidence is provided that deviations are measured from an exogenous source independent of the return series itself. The attribution therefore reduces to a definitional restatement rather than an explanatory mechanism.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption Levered ETFs target constant daily leverage but exhibit deviations in practice.
Reference graph
Works this paper leans on
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[1]
M., Bianchi, S
Anderson, R. M., Bianchi, S. W. & Goldberg, L. R. (2012), ‘Will my risk parity strategy outperform?’, Financial Analysts Journal68(6), 75–93. Anderson, R. M., Bianchi, S. W. & Goldberg, L. R. (2014), ‘Determinants of levered portfolio perfor- mance’,Financial Analysts Journal70(5), 53–72. 3https://www.proshares.com/globalassets/proshares/fact-sheet/prosha...
2012
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[2]
Jarrow, R. A. (2010), ‘Understanding the risk of leveraged etfs’,Finance Research Letters7(3), 135–
2010
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[3]
Lenkey, S. L. (2024), ‘The market impact of leveraged ETFs: A survey of the literature’,Quantitative Finance and Economics8(4), 815–840. Lettau, M. & Madhavan, A. (2018), ‘Exchange-traded funds 101 for economists’,Journal of Economic Perspectives32(1), 135–154. Madhavan, A. N. (2016),Exchange-traded funds and the new dynamics of investing, Oxford Universi...
2024
discussion (0)
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