The Japanese stock market has rebounded smartly since the earthquake struck on March 11. But many investors who used exchange-traded funds to capture those gains may have been sorely disappointed.

Since a March 15 low, the three US-sold ETFs that track the broad Japanese stock market all have lost money, even though the indexes they mimic are up. The largest, the $7.2bn iShares MSCI Japan Index ETF, has lost 0.6%, even though the MSCI Japan index, which the fund tracks, is up 5.3%.