UPDATE 1-Oil ends 2015 in downbeat mood; hangover to be long, painful

* Crude oil prices lost a third in value in 2015 * Outlook for 2016 remains bleak as oversupply balloons (Adds commodity performance chart, updates prices) By Henning Gloystein SINGAPORE, Dec 31 (Reuters) - Oil prices remained in a downbeat mood during their final Asian-hours trading session of 2015 after record U.S. crude inventories reinforced concerns about a global supply glut that has pulled down prices by a third over the past year. Crude inventories in the United States