Greek life at Colgate according to Common Data Sets posted on their website:
2013-14 men 31%, women 35%
2009-10 men 32%, women 29%
2006-07 men 33%, women 29%
There obviously has not been some precipitous dropoff, in fact sorority membership increased 20% over the most recent 4 years. 2013-14 is the most recent Greek data posted. Whoever at Colgate made the comment about significantly lower Greek participation had nothing to base it on.