The KBW Regional Banking Index is not the underlying index for KRE, the largest regional bank ETF, so investors should expect the daily moves for KRE and KRS to have a perfectly negative correlation. Rather, the KBW Regional Banking Index is the underlying index for the PowerShares KBW Regional Banking Portfolio (NYSE: KBWR). KBWR was able to eke out a small gain Wednesday, but the fund lost 2.17% Thursday.

Investors may want to give KRS a look if lower interest rates continue to adversely affect regional banks, though it should be noted KRS is not heavily traded with average daily volume for the trailing three months of about 2,950 shares.

ProShares Short KBW Regional Banking

ETF Trends editorial team contributed to this post. Tom Lydon’s clients own shares of KRE.