=LEFT(B2,4)
=MID(B2,FIND("年",B2)+1,FIND("月",B2)-FIND("年",B2)-1)
=MID(B2,FIND("月",B2)+1,FIND("日",B2)-FIND("月",B2)-1)

12,11,10,9,8,7,6,5,4,3,2,1
1,2,3,4,5,6,7,8,9,10,11,12