The stock shot up 43.5% on Wednesday, the stock's biggest-ever one-day gain, to close at a more-than 5-year high on record volume of 90.3 million shares. That was the stock's fifth-straight gain, with the stock soaring 112% over that time. At Wednesday's closing price, J.P. Morgan Chase's stake was worth $356.4 million, but was now worth $229.2 million.