I don't do that kind of financial modeling so I'm unsure if your colleagues suggestion itself is on target.

Logarithms are the inverse function to exponentiation. For example:

log\_2 16 = 4

which would be read "log base 2 of 16 equals 4"

with the relationship being 2\^4 = 16

and in general

log\_b x = y implies b\^y = x