Oh no, it is the average value. You don't want to know the lowest value. Or if you do, go to the Spanish utility's site and browse statistics for the summer months, when wind is usually slower:
You're right. Anyway, and what I mean, is that the average of energy provided with enough wind is pretty high. The average isn't that low for the 95th percentile (and the bottleneck is still the wind)
http://www.ree.es/ingles/operacion/curvas_eolica.asp
E.g. July 1st 2009 - minimum of 105 MWe, or about 0.3% of average demand. The recent peak was 11,500 MWe:
http://www.guardian.co.uk/environment/2009/nov/09/spain-nati...