Assessing Securities Lending Risk-Return Performance in a Portfolio Context
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Asset-Based Lending Assessing Securities Lending Risk-Return Performance in a Portfolio Context by Ben Atkins and Glenn Horner hile many institutional investors embrace paying a rebate rate on this cash collateral.1 Demand securities lending as an attractive tool to to borrow securities usually causes the rebate rate to enhance portfolio returns, others remain wary. fall below the risk-free rate (the line). For some secu- WMany perceive securities lending to be an eso- rities, this spread is quite substantial; the demand teric distraction—a tool limited by risky, immaterial spread represents the “specialness” of a security to returns. State Street addresses the latter view by borrowers. Some lenders are content with the grounding investors’ performance analysis on risk- demand spread; they simply invest the cash collateral adjusted returns. The data lead to two key conclu- in Treasury repo. Most lenders, however, seek addi- sions for investment managers and plan sponsors: tional returns by investing the collateral in high-qual- 1. Although securities lending returns are relative- ity money market instruments (collateral reinvest- ly small, superior risk-adjusted performance ment).2 In this way, they capture reinvestment highlights its value. returns by assuming a limited degree of credit and 2. Managers may optimize their lending program through a broader framework that integrates the Figure 1 risk-return performance of the underlying Disaggregation of Securities Lending Returns investments. Increasingly, investors focus on minimizing Reinvestment return “frictional” losses due to management fees, commis- sions, and inefficient trading. A well-structured lend- Reinvestment spread ing program represents an attractive tool to offset Risk-free rate some of these losses. Demand spread An assessment of securities lending risks requires disaggregating program returns into two Rebate rate components: 1) demand, or “below-the-line,” spread; and 2) reinvestment, or “above-the-line,” spread. Depicted in Figure 1, this framework derives from the lending transaction. Typically, a prime broker (the borrower) provides cash collateral to borrow a security; the lender compensates the borrower by © 2006 by RMA. Ben Atkins, CFA, FRM, is a manager in the Corporate Initiatives Group, General Electric Company, in Fairfield, Connecticut; formerly, he was Asset- Liability manager at State Street Bank. Glenn Horner, CFA, FRM, PRM, oversees Portfolio Strategy and Quantitative Modeling for State Street’s Securities Finance Division. 42 The RMA Journal May 2006 Assessing Securities Lending Risk-Return Performance in a Portfolio Context Figure 2 Comparison of Risk Statistics Standard Deviation Skewness VaR4 Worst Excess Return Securities Lending Demand spreads 0.006% 0.7 0.01% 0.00% Reinvestment: overnight5 0.004 0.0 0.01 -0.01 Reinvestment: money market5 0.02 0.4 0.04 -0.05 Bond Indexes Lehman Brothers U.S. 1.29% -0.6 2.53% -4.23% Lehman Brothers U.S. Credit 1.35 -0.4 2.24 -4.36 Lehman Brothers Global Aggregate 1.68 0.3 2.70 -3.74 Stock Indexes S&P 500 4.73% -0.5 8.48% -14..90% Russell 2000 6.28 -0.5 8.93 -19.84 MSCI EAFE 4.56 -0.5 8.09 -12.97 Data period: monthly returns from 1/1/98 through 7/31/2005 (n = 91) Source: State Street SL PerformanceAnalyzer®, LehmanLive.com, Bloomberg, State Street analysis duration risk. Analyzing both of worst-return measures indi- fees, which can be 20-50 basis these return components reveals cate that securities lending points. On this scale, lending the relatively low levels of market resulted in minimal down- returns appear more substantial. risk in securities lending. side exposure compared to In a more rigorous approach, risk- We have studied 7.5 years of major benchmarks.6 adjusted return analysis quanti- lending data. During this period, This analysis highlights the large fies the risk-return trade-off. securities lending was consider- disparity between market risks in An analysis of risk-adjusted ably less risky than familiar mar- investment benchmarks and performance asks: Do returns ket indexes. Figure 2 compares securities lending. adequately compensate an risk data from State Street’s lend- A cynic may respond to investor for the level of portfolio ing program with several key Figure 2, by saying, “Yes, the risk? The Sharpe ratio addresses benchmark indexes.3 Several con- securities lending volatility is this question through a cost- clusions emerge: trivial, but so are the returns.” benefit approach: 1. The volatility of securities Some investment managers con- lending returns—the stan- clude that lending returns are dard deviation—was trivial immaterial compared to bench- Rp - rf compared to levels experi- mark returns, but the comparison S = enced in key benchmarks. is spurious. Active managers do p 2. The skew statistics show that not provide the benchmark extreme returns over the last return—they add value by seek- 7.5 years of lending tended ing alpha—incremental perform- With Rp the portfolio return, to be in excess of the mean, ance in excess of the rf the risk-free rate, and p the while extremes in bench- benchmark.7 Top managers deliv- standard deviation of portfolio mark returns tended to be er 100-400 basis points of alpha. returns; this ratio may be inter- unfavorable. Similarly, passive managers preted as the excess return pro- 3. The value-at-risk (VaR) and emphasize low tracking error and vided for each unit of volatility.8 43 Figure 3 Analysis of RIsk-Adjusted Performance Mean Excess Return (annualized) Sharpe ratio Securities Lending Demand spreads 0.21% 10.1 Reinvestment: overnight 0.02 1.6 Reinvestment: money market 0.24 2.8 Bond Indexes Lehman Brothers U.S. Govt 2.47% 0.6 Lehman Brothers U.S. Credit 3.05 0.7 Lehman Brothers Global Aggregate 2.45 0.4 Stock Indexes S&P 500 1.19% 0.1 Russell 2000 3.75 0.2 MSCI EAFE -0.28 0.0 Data period: monthly returns from 1/1/98 through 7/31/2005 (n = 91) Source: State Street SL PerformanceAnalyzer®, LehmanLive.com, Bloomberg, State Street analysis Figure 3 provides a key finding: 3. The money market reinvest- this finding should further reduce Lending returns were smaller than ment strategy drives superior concerns about securities lending market index returns, but lending risk-adjusted performance by market risk. If, for example, an offered superior risk-adjusted per- capturing additional returns investor suffers losses from a formance over this time period. through modest exposure to Russell 2000 portfolio, lending Both sources of securities duration and credit risk. does not amplify these losses. lending returns—demand and On a stand-alone basis, the Over time, lending returns offer a reinvestment spreads—contribute demand and reinvestment spreads small dampening effect for overall to this conclusion. Taking each represent a compelling source of volatility. component in turn: low-risk, incremental returns. Construction of an efficient 1. The high Sharpe ratio for Securities lending also performs frontier offers a useful synthesis of below-the-line returns stems well when viewed within a broad- the benefits of securities lend- from borrowers’ stable demand er portfolio context. ing—low-risk incremental returns for securities. As one invest- Specifically, correlation analy- with low correlation to investors’ ment manager remarked, sis demonstrates that lending portfolios. Figure 5 shows how “The demand spread looks returns provide modest diversifi- lending returns have expanded like a free lunch.” cation by exhibiting zero correlation the efficient frontier.9 The lower 2. The overnight reinvestment to benchmarks. Figure 4 provides frontier depicts, for a given level strategy achieves a favorable the correlation coefficients for the of volatility, the maximum excess Sharpe ratio by earning a components of lending returns monthly return earned with the small, nearly fixed spread by with the returns from a composite optimal allocation across asset assuming incremental credit index of underlying lendable classes. Using typical on-loan uti- risk on the collateral. Speci- assets. A correlation less than 1.00 lization levels, the higher frontier fically, reverse Treasury repo leads to a reduction in the overall shows that lending increases sets the risk-free rate, and the portfolio’s volatility. This effect monthly returns by 0.5-1.5 basis 2-basis-point spread repre- increases as the correlation falls to ponits across a range of alloca- sents a weighted average of zero; correlations less than zero tions.10 Lending improves the repo spreads for lower grades indicate that returns tend to vary efficient frontier by consistently of collateral (e.g., agencies, inversely with the underlying adding incremental returns, while mortgage-backed securities). portfolio. The effect is small, but reducing the volatility of the over- 44 The RMA Journal May 2006 Figure 4 Correlations of Returns from Lending and Underlying Portfolios Reinvest Spread— Demand Spread Reinvest Spread—Overnight Composite of Client Assets Short-term Demand Spread 1.00 Reinvest Spread—Overnight (0.48) 1.00 Reinvest Spread— (0.12) 0.03 1.00 Short-term Composite of Client Assets 0.05 (0.01) (0.10) 1.00 Note 1: Composite of client assets represents the asset-weighted returns from the Lehman Brothers US, Europe, and Asia bond indexes; MSCI North America, Europe, and Asia Pacific equity indexes Note 3: Correlation uses monthly returns from 1/1/98 through 7/31/2005 (n = 91, DF = 89) Source: State Street SL PerformanceAnalyzer®, LehmanLive.com, Bloomberg, State Street analysis all portfolio. Graphically, the adjusted performance. opposite strategy of the Overnight Sharpe ratio is the slope of the Figure 6 outlines several column. Investors with high risk line from the origin to the risk- approaches to developing a col- tolerance lend securities to return point on the graph. lateral reinvestment strategy. A finance purchases to replicate the Lending steepens this line by program that restricts collateral exposures of the underlying port- shifting the endpoint up and to reinvestment to overnight repo folio.