I have a column of data with 10,000 data items with some repeats. I want to only pull out the first instance of each of these and do a count of them.

Ideally, I should have a function to input a 1 next to the first instance of each item. I can use that whole data set in a pivot table and count the number if 1's to find out the unique instances.

I could pull out unique instance via the advanced filter but that won't work with the pivot table.

Can anyone help me out with this?

Thanks,
Neel.