Banks, represented here using the KBW Bank Index, ended up underperforming the the S&P 500 by about 375 basis points in 2014. Since the beginning of 2015, bank performance has been much worse. So far this year the KBW Bank Index has underperformed the S&P 500 by a whopping 753 basis points in a little under three weeks. Over a longer term perspective (20 years), the KBW Bank Index has underperformed the S&P 500 by over 40%.