Sensex ended the session at 80,364.94, down 61.52 points or 0.08 per cent. The 30-share index started the session in green at 80,588.77 against last session's closing of 80426.46. The index remained range-bound despite buying in the broader market. It hit the intra-day high and lows at 80,851.38 and 80,248.84, respectively.