CONVERT worksheet formula into vba code

Hi

I'm manually entering a 10 digit code into Col A; at this moment in time I have the following formula in Col B:

DATE(2000+MID(A13,6,1),LOOKUP(MID(A13,5,1),{"1","2","3","4","5","6","7","8","9","X","Y","Z"},{1,2,3,4,5,6,7,8,9,10,11,12}),MID(A13,3,2))

However I have to drag and fill all the cells in Col B with the formula - is there anyway of just entering the code into Col A and excel automatically inderts the result based on the above formula into Col B? VBA coding??