Garret,
This is just a guess...
It looks like when you are adding the value from the screen, it is using the recordID as opposed to the text value of the field. You can test this theory by seeing if your RecordIDs are off by 1 number in the table that contains 1-10. For example the number 2 would be recordID 3.
When you use the retrieve value from screen action, you have the choice to select the dropdown attribute, with the basic math calculation, you do not have this option.
Hope thats makes sense.
Matt Raiser
Founder,
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matt@techinthefield.com
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