VBA Errors

Hi

I have inhertited a workbook with VBA script already detailed out. I am adding the following code to populate my worksheet with my required formula once the report is run from our MIS

Sheets("Analysis").Select
Dim n As Integer
n = ActiveSheet.Range("A1").End(xlDown).Row
Range("a2").Select
Selection.AutoFill Destination:=Range("a2:a" & n)

Each time I try and run the report I get one of the following errors

Error 1004 : Autofill method of range class failed
Error 6 : overflow

I am not familiar with VBA to fully understand where the problem lays. Attached is my worksheet. I am taking the information from our MIS which will be published in Student Data and pulling the information I want into my Analysis tab (where the formula is).

Can anyone help?