The Sensex at the Bombay Stock Exchange soared by 574 points to 20,536 in opening trade. National Stock Exchange's Nifty also gained by 184 points to 6,083.The rupee today zoomed by 158 paiseto trade at over one-month high of 61.80 against the dollar at the Interbank Foreign Exchange market on hopes of increased capital inflows after the US Federal Reserve's surprise decision to keep its stimulus programme intact.The rupee had settled just a paise lower at 63.38 against the dollar in yesterday's trade.