Thank you. That worked.
I have another problem. In an Acrobat 11 form I have 35 drop down fields that for example have the following choices, N/A, 5, 0. Each N/A has a value which is the highest number in the choices. In my example this one would be 5. I want to sum the value of all N/A choices.
There are not any calculations available within the form - but you can use formulas in the View Response tabs Response Table.
Here are some resources for formulas, note that the how to only shows using the formula in a row but you can use them in a row or a column: