Canadian DVD Rental Info pages
This calculator assumes 21 business days per month, and that the company ships a new movie back out the same day it receives one from you.
If you take advantage of ZIP's ZipRefill feature or Canflix's Flix Return, your potential average will be higher, as they will in some cases ship discs before your return arrives. The exact increase will depend on your actual transit cycles in a given month. Cinemail's similar Quick Return feature is available 4 days after a disc is shipped, so you can best estimate your average when it is enabled by setting the "Average Shipping Days" value to 2.