Serena from SerenaSmithLampwork says
so, as i understand it, for example if your shop has 200/20,000 total sales/$ but only 100/10,000 went through paypal, and 100/10,000 went through direct check out, then you wouldn't pass the threshold for either.
Yes, this is correct. It's the amount of many that goes through each payment center, not your total sales on the site.