Wall Street pros are more bearish on stocks than at any point since 2008. Here's why that might be great news for investors.

• Investment pros on Wall Street are now more bearish on stocks than they were during the 2008 crisis.
• Sentiment data from Bank of America shows equity allocations among Wall Street market strategists has fallen below 53%.
• "It has been a bullish signal when Wall Street strategists were extremely bearish," BofA said.

Investment pros on Wall Street are getting more and more bearish on US stocks, according to a Monday note from Bank of America, but that downbeat mood could be flashing a big signal to investors that it's time to buy. 

In fact, Wall Street strategists are now more bearish on stocks than at any point since the Great Financial Crisis in 2008 and 2009, according to the note.