Originally Posted by PhDV

I dont think that there is something like average conversion rate for affiliate programs.
It depends on whether it is niche or mainstream, has trial or not and many other parameters.
+ it also depends on traffic sources. Review site get something like 1:50, 1:100
But mainstream tube site may have ratios around 1:1-2K and worse.
Even if you calculate an average ration within one affiliate program it wont make much sense