Any such assessment largely depends on your definition of "state-funded terrorism". Saudis, for example, fund a massive network of Salafi religious schools all over the world, that has a very impressive record of radicalizing their students. Said students then end up running organizations like Caucasus Emirate or Daesh, or just blowing up local targets of opportunity (including moderate Muslim clergy that is trying to actively counter Salafi propaganda in their area, thereby preventing or at least limiting further radicalization).

But most importantly, I was asking about US. How many terrorist groups in US does Iran fund, and what damage have they done to date?