The worst recession since the 1930s is over, according to two of the world’s richest men. Famed investor Warren Buffett told an audience of business students in New York: “The financial panic is behind us. Our economy was sputtering. And still is sputtering some.” And he added that the US was the best place for investors to put their cash. He was joined at Columbia University by Microsoft founder Bill Gates who said the collapse in the economy “proved that we can make mistakes”.