How do you test the efficiency of an antivirus system?

Answer 1

Basically it is done by testing all possible scenarios.

Real world result are completely surprise for new vulnerabilities but Antivirus uses generic definition of viruses which could possibly detect billions of newly created Viruses.

You can look online for different tests with description.

Answer 2

This is what I' trying to find out.
Like how would they test this software at the development stage.
Looking for specific answers lol
Do you think I should email a company and ask ?