Is polyamory actually higher amongst LW people than the general population?

This made me realize I didn't even know whether there were reliable estimates of polyamory prevalence in the general population. A cursory Google Scholar search didn't net me anything, but the Wikipedia article has a data point:

Research into polyamory has been limited. A comprehensive government study of sexual attitudes, behaviors and relationships in Finland in 1992 (age 18-75, around 50% both genders) found that around 200 out of 2250 (8.9%) respondents "agreed or strongly agreed" with the statement "I could maintain several sexual relationships at the same time" and 8.2% indicated a relationship type "that best suits" at the present stage of life would involve multiple partners.

Meanwhile, 13% of LWers in the 2012 survey said they preferred polyamorous relationships, although only 6% reported having multiple current partners. While 13% is appreciably higher than the Finnish survey's 8%-9%, the discrepancy could just be because the Finnish survey's from a different time & place and has a more even gender ratio.