AUTO FILTER - can manual row numbers re-number themselves?

[itr674]

I have a project where I have numbered the rows starting at A10 down to A1000. So the numbers go from 1 to 1010. If I auto filter for a certain office and it pulls up 50 rows would it be possible for the row numbers to re-number themselves in column A to show 1 thru 50 for that particular office--and then when the auto filter is removed the numbers would revert back?

 

[z168]

reviving an old thread

I cant make the UDF work. Help

 

[z168]

UPDATE: need to sharpen my search skills

here is the answer

Thanks