The most salient group is the oil bull market, which had been in retreat since 2014. It has now come back fiercely in a move that Cramer attributed to that of FANG — Cramer's acronym for Facebook, Amazon, Netflix and Google-parent Alphabet — except oil has a much larger impact on the market.
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"Oil has got ramifications that are much broader than the stocks themselves. It has become the ultimate barometer of the pressure in the system," Cramer said.
When oil goes down, many investors assume that banks are threatened, China is stalling and dividends are in danger. Instead, it went up on Wednesday, which was the bull market move that Cramer wanted to see.
Initially the move only embraced Exxon and Chevron, but then extended to oil service company Schlumberger, now the big international oils are getting in on the action. French giant Total and BP have gained strength to head higher.
Cramer also considers financials to represent the pulse of the market. With the global economy stabilizing and the labor market strong, the Fed's decision to remain unchanged on Wednesday ensured that JPMorgan and Wells Fargo got a lift.
The banking cohort has been able to rally ever since oil crossed above $40, and Cramer didn't see any signs of it quitting.
"Why not, the bank stocks are real cheap, they have been left behind by the rest of the market and the Fed is giving everyone a positive spin," Cramer said.