(Washington, DC) -- There's a new rule that restricts banks from making big trading bets with federally insured deposits.

Today five federal agencies approved what's known as the Volcker Rule, which shuts down what was a hugely profitable business for Wall Street before the credit crisis.

The rule was a central element of the 2010 Dodd-Frank financial reform bill and is named after former Fed chairman Paul Volcker. The rule is expected to eat into revenues at large investment banks such as Goldman Sachs and Morgan Stanley.