The Impact of Benchmark Choice on US Mutual Fund Benchmark-Adjusted Performance and Ranking

Abstract

This study re-visits the question of benchmark mismatch among 1281 US equity mutual funds and its impact on benchmark-adjusted fund performance and ranking. All funds report S&P500 index as a prospectus benchmark, yet 2/3 of those are placed in the Morningstar category with risk and objectives different to those of the S&P500 index. We identify ‘true’ benchmarks for those mismatched funds and find that their S&P adjusted alphas are higher than ‘true’ benchmark adjusted alphas in 61.2% of the cases. In terms of fund quartile rankings, 30% of winner funds lose that status when the prospectus benchmark is substituted with a more suited one. In the remaining performance quartiles there is no clear advantage of using S&P 500 as a prospectus benchmark. The prospectus benchmark therefore can mislead investors about fund’s relative performance. This leads us to conclude that any reference to performance in a fund’s prospectus should be treated with caution.