From NY Gaming Commission Rule 4011.26(h):

(h) Race cancellations. Except for pick-six pools in which an intermediate or final distribution is to be made, should one or more pick-six races be cancelled or declared no race or non-betting, no carry-overs from prior pick-six pools, advertised guaranteed amounts nor advertised added amounts will be distributed to winners in such day's pick- six pool; and

(1) if more than three such races are contested, 75 percent of that program's net pool shall be distributed, less breaks, to holders of wagers upon the winners of all the contested pick-six races and 25 percent of such program's net pool shall be distributed to the holders of wagers selecting the next most winners; should no wager select the winners of all the contested pick-six races, 25 percent of the net pool shall be distributed, less breaks, to the holders of wagers selecting the most winners of the contested pick-six races, and 75 percent of such program’s net pool shall be carried over as elsewhere provided in this section;

(2) if three or fewer such races are contested, then entire pool for such program shall be refunded; and