COLLIERS INTL GROUP INC revenue for the last year amounted to 6.91 B CAD, the most of which — 4.21 B CAD — came from its highest performing source at the moment, Real Estate Services. The greatest contribution to the revenue figure was made by United States — last year it brought COLLIERS INTL GROUP INC 3.53 B CAD, and the year before that — 3.19 B CAD.