The Danger of Indices

 | Feb 02, 2015 12:59AM ET

We’re surrounded by investment products that track indices. S&P 500 index funds seek to replicate the performance of the S&P 500 index – easily accomplished by simply buying the constituent stocks in designated weights. Other indices are more difficult to track – for example when the product invests in futures to approximate spot market returns (GSCI) or acquires only a subsample of index constituents (Barclays Ag).

A new generation of indices promises to emulate more complicated investment strategies, such as currency carry, volatility and roll trades. Investment banks now offer institutional investors an array of derivative products tied to such indices, and asset managers are packaging them into ETFs and other fund products.

One problem, however, is that newly created indices tend to overstate historical, hypothetical performance. From a commercial perspective, there’s little point in launching a new index if the pro forma returns are unattractive; consequently, there’s a strong incentive to adjust the calculation methodology until the results look favorable.

Further, unlike mutual funds, indices can be created and published with minimal disclosure of key information, such as when the index went “live” and what assumptions are made about trading and other costs. The combination can mislead investors who may expect actual net of fee fund returns to match hypothetical gross of fee index returns.

A case study is the PowerShares Multi-Strategy Alternative Portfolio fund (LALT), an active ETF launched at the end of May 2014. This Fund seeks to match or outperform the Morgan Stanley Multi-Strategy Alternative Index (Bloomberg ticker MSUSLALT), comprised of a combination of risk premia strategies designed to deliver absolute returns.

h2 Unrealistic historical index returns/h2

On Bloomberg, the Index data begins on 1/1/2003. Given the start date, it is possible that the Index was launched sometime in 2013 with roughly ten years of backfilled data. Unfortunately, there is no requirement to differentiate between backfilled and live results, and neither the LALT prospectus nor Bloomberg sheds any light on when the Index went “live.”

The backfill thesis is supported by historical performance. The following chart shows the Index returns for the ten years preceding the launch of LALT against the S&P 500 and HFRIFOF index.