There are really 10 rides over 10 months, Feb to Nov, which line up fairly well with the full moons. In addition there are three extra rides in the list, giving two rides in each of June, July, and September. Those three might be anticipated to be less popular for one reason or another.
The full moon dates are:
February 28, 16:38
March 30, 02:25
April 28, 12:18
May 27, 23:07
June 26, 11:30
July 26, 01:37
August 24, 17:05
September 23, 09:17
October 23, 01:36
November 21, 17:27