Can I selectively export fields to google spreadsheets?

I have a form which has a number of hidden fields that are only shown when other conditions are met.  For example, I have two sets of 3 fields, where only one of the 3 will ever be filled.  That is, depending on which state is selected, I show one of 3 'State Place Finish' fields.  Is it possible to only export the populated field?

I would suggest creating a report and uncheck the field that you do not want to include in the final file. You can create a report in CSV or Excel format:

https://www.jotform.com/help/101-How-to-create-an-Excel-Report

https://www.jotform.com/help/103-How-to-create-a-CSV-Report