Jim Cramer has witnessed institutional investors suddenly pouring money into groups that have stalled and been neglected.
These very big sectors have suddenly come alive, and he says it could mean good things for the stock market.
"The banks, the oil service companies and the airlines. All groups that the market had given up on for the last year, all inching back, all primed to explode higher if just a few more things go well," the "Mad Money" host said.
Banks account for a large portion of the S&P 500, yet their performance has lagged the S&P dramatically this year as investors wait for the Federal Reserve to raise interest rates. When interest rates go higher, banks make more money because they collect higher rates from customer deposits.