Growing concerns about the fallout in the subprime mortgage market caused heavy selling in banks and brokers today. Today's selling more than wiped out yesterday's rebound in the financial group. Chart 1 shows the Financials Sector SPDR (XLF) undercutting yesterday's intra-day low. It's now threatening its 200-day moving average. Most of the selling came in brokers and money center banks most directly affected by subprime problems.