Macro to automatically fill cells based on previous entries

Hey guys!


In my new job I have to work a lot in Excel. To make my question simple to understand I'll ask with a simple example:

ColumnA ColumnB
Jan 1
Matej 2
Renata 3
Andrej 4

If I have it like this, basically what I need is a macro that checks everytime I fill ColumnA if there is already a duplicate entry in the same column and fills the value of ColumnB accordingly. So if i write in ColumnA "Jan" that it would fill ColumnB next to it by 1. Or if I write "Renata" it would automatically fill the ColumnB next to it by 3.


Thanks!
Jan

Hi
B5=IF(ISERROR(VLOOKUP(A5,$A$1:B4,2,FALSE)),B4+1,VLOOKUP(A5,$A$1:B4,2,FALSE)) Drag the formula down to the last entry.This will return the first match only.
Ravi