Shares of real estate companies were buzzing in trade and prompted a sharp up move in the Nifty Realty index, which leaped to its highest level in 15 years on strong housing demand. Nifty Realty index was quoting at its highest level since September 12, 2008. In Thursday's trade, it hit an intra-day high of 621.65, up 1.3 per cent, surpassing its latest 52-week high of 619.90 touched on October 13.