Impressive...

Another alternative:

=INDEX($B$3:N$3,MATCH(2,INDEX(1/(LEFT($B$1:N$1,4)="Year"),0))-1)-SUM(INDEX($B2:B2,MATCH(2,INDEX(1/(LEFT($B$1:N$1,4)="Year"),0))-12):INDEX($B2:N2,COLUMN()-14))