divergence

The drooping stocks of investment banks and brokerages have been diverging from the wider market in the last few months. Back in 2007, a similar trend preceded the market crash. Now, the sector's pattern could hold a wider warning for investors.

Numerous analysts have questioned the foundations of the current stock market rally, but the sagging economy hasn't stopped the rally from chugging into its ninth month. On Monday, the market charged out of the gate and held on to a three-digit gain all day. Though the rally has ground down all...