NEW YORK (Reuters) -JPMorgan Chase boosted its outlook for investment banking revenue, forecasting a jump of 25% to 30% in the second quarter fueled by capital markets, a top executive said on Wednesday. The forecast became more bullish than in May, when the bank predicted investment banking revenue would rise by a mid-teens percentage in the second quarter. "Capital markets continues to be extremely robust and the overall franchise has improved," said Troy Rohrbaugh, co-CEO of JPMorgan's commercial and investment bank.