Mutual fund investors must be kicking themselves. For the two business days ended Tuesday, Jan. 2, fund investors pulled an estimated $15.9 billion out of equity mutual funds, according to

TrimTabs.com.

Indeed, TrimTabs.com estimates that equity mutual funds saw their

biggest outflows ever on Tuesday, as mutual fund investors pulled $13.1 billion from the market. The huge outflows could not have come at a worse time, as the Fed eased interest rates on Wednesday, vaulting the stock market to huge gains. The

Nasdaq

, in fact, was up more than 14% on Wednesday, its biggest one-day move ever.

U.S. funds saw estimated outflows of $13.14 billion for the two days ended Tuesday; international funds saw estimated outflows of $2.79 billion.

During the two market days ended Jan. 2, the

Nasdaq

fell 9.8%, the

Dow

dropped 2.1% and the

S&P 500

slipped 3.8%.