Month,X1,X2,Sales
Jan,11,14,49.4
Feb,8,11.8,47.5
Mar,11,15.7,52.6
Apr,14,15.5,49.3
May,17,19.5,61.1
Jun,15,16.8,53.2
Jul,12,12.8,47.4
Aug,10,13.6,49.4
Sep,17,18.2,62
Oct,11,16,47.9
Nov,8,13,47.3
Dec,18,20,61.5
Jan,12,15.1,54.2
Feb,10,14.2,44.7
Mar,13,17.3,53.6
Apr,12,15.9,55.4