I have never worked it out, but I don't pay much. The owner of my local shop usually hooks me up with a chunk of wax for $10.00 off of the bulk team wax, and that usually lasts me a couple of seasons. Even when I buy the expensive stuff it lasts me years. But keep in mind nowadays with a kid I go like 2 -5 times a year.
If I had to guess it has to be like $0.17 - $3.87 depending on the bulk wax or pre packaged flouro.