Swedish to English Science Mathematics & Statistics

I am working on the translation of a research paper on pesticides which includes a handful of formulae. These are really outside of my expertise, so I would appreciate some input from someone who has experience in this mathematics/science.

What I am unsure of is whether these formulae refer to something in Swedish, and hence need to be translated, or whether they can remain as they are.

The formula in question is this MAF=(1-enki)/(1-eki)

It appears in the following context:
"MAF för akut bedömning beräknad av KemI enligt formel MAF=(1-enki)/(1-eki), eftersom defaultvärde för 90:e percentilen i vägledningsdokumentet saknas för tidsintervallet 21 dagar."

I think that "MAF" means "Million acre-feet", referring to the surface area over which the pesticide is spread, but I am also open to other suggestions if this does't fit with the formula.

Thanks in advance for any advice you can offer.