Here's my thesis on the coasters I count:
- Any coaster that I have ridden from my birth to this very second is in my count. That way, rides like Dragon Wagon at Galaxyland that I'm much too large for nowadays can still be included.
- I count coasters at fairs/carnivals. For example, I rode a Zyklon at the state fair in 2016, but there was another one that I rode at the fair in 2017. Since I could tell there was a significant visible difference between the two, I counted these as two different coaster credits as opposed to one or even none.
- Clones and dual tracked coasters count, even if they're a Mobius loop. One track = one credit. As for clones, well,
- If I've ridden the relocated coaster at two of its homes or more, that would only count as one credit. Think about it - if you're taking a coaster away from a park (-1) only to be added to another (+1), it cancels out at 0.
- Although they aren't constantly propelled by gravity, I do count powered coasters because during the downhill parts of their circuits they are indeed moved by gravity.
As you can see, I'm very basic in what I constitute as a credit versus what I don't consider a credit. I don't count Skywarps, Superloops, or the High in the Sky Seuss Trolley Train Ride at Universal's Islands of Adventure towards my count, though.