Membrane test results

I just received my membrane back from CDL after they washed it and I'm a little confused with the test results.
Results are "passing sugar 0% / Performance before 92.1% / Performance after 84.4%"
Why did the performance go down after the wash? Shouldn't it at least be the same or better? Also, at what point do I start thinking about replacing it?

Did you ask them about it? Maybe they just reversed the numbers. It should be better after a wash in theory.

No I haven't talked to anyone yet. Paperwork just came in the mail today. I opened it after I got home from work.

Ask them or maybe your CDL dealer.