Investment banks' trading revenue declined 9 pct in 2015 - survey
* FICC revenue at 12 top banks $69.9 bln last year - Coalition * Compares with $109.1 billion five years before * Commodities revenues drop 18 percent * Equity business is rare bright spot, revs up 10 pct to $50 bln By Anjuli Davies LONDON, Feb 22 (Reuters) - Revenue
