About how much does the Annual Passes cut off of the tickets. What I mean is how big of a discount is it compared to the regular priced tickets. I'm interested in this information.
It depends. The lowest passes get no discounts, the middle of the road passes (that I have) is 10%, the higher pass I think gets more of a discount. Sometimes, there are "AP Perks" promotions where all passes get 15% off.
BUT BUT BUT, you can't use them to buy tickets online. They'll just tell you, "the discount is already included versus the gate price". At least that's my experience. You used to get discounts on HHN tickets, but haven't been able to for years. Hearing that Alicia got a discount for RIP is interesting. I've never done that tour so don't know, but for the last decade or so our RoF+Express and UTH tickets were not subject to AP discounts. Take my nephew to Universal every year and when I book our room and stuff and try to give them my AP number for getting him a ticket, they tell me they can't.
So in terms of regular park tickets, it's really just a discount if you walk up to the window day of to buy tickets...and that gets it down to about the price when you purchase online in advance.
EDIT: Should add that sometimes they offer huge discounts, like for the "Taste of HHN" or whatever they had last year, they offered significant discounts (I think like $35). And for stuff like the Mari Gras parade float riding, they offer a FREE sign up for that (which, including a meal, cost about $90 per person without an AP) but those were gone in like an hour. I think they offered a daily stand-by line for AP holders to possibly get into that day's parade if there openings available.
So there's no clear cut answer, and need to put in the caveat that I only go to Universal twice a year and don't really know the ins and outs of all this stuff, so this is all just my experience.