Jan ( N = 496 )
Feb ( N = 447 )
Mar ( N = 496 )
Apr ( N = 461 )
May ( N = 489 )
Jun ( N = 480 )
Jul ( N = 496 )
Aug ( N = 495 )
Sep ( N = 480 )
Oct ( N = 493 )
Nov ( N = 480 )
Dec ( N = 494 )