To create a drop down list as a filter with a calculation

I would like to create a drop down list a s a filter to choose a few buckets - calculated field needed.

As a filter I would like to show currencies in my wallet.

If amount of $ = 0 then $ 
if amount of € > 0 then €
if amount of £ > 0 then £
if amount of $ is > 0 then $

how do I get that without any errors ? I would like that formula to start 'searching' in data source over again after each line.

As a result in filter I would like to choose the currencies.