Yeah, that's what "input clamping" means: disregard any runs older than 100 days. I only brought it up because the max(...,0) thing becomes totally unnecessary if you clamp the input properly (actually, so does min(...,1)), so I thought maybe they weren't.

The real issue here is that this function hits 0 at 70 days, when it's meant to be 100.

Back in high school, I got all my friends on an anagram kick. When I plugged my own name into the anagram finder, naturally I got a bunch of funny but meaningless results. Except one...

[Something] Warm Cabin.

Warm Cabin! That's, like, a reasonable phrase you might hear! And who doesn't wanna go visit a nice warm cabin!?
I went by [Something] Warm Cabin for years, until I decided to shorten it to warmCabin. Partly because it's more slick, and partly because it was my full name...

The weird capitalization is called "hump capitalization," and it's a programming thing--variable names usually get capitalized like this. It's also a Homestuck thing.

I know I'm late, but...
This is the function you've described (where R = number of days since last run). It hits 0 after only 70 days, and actually starts to rise again after 130. Even with input clamping, it doesn't do quite what you described.

This is a nice alternative. Gives you the quadratic falloff you were going for...but it's secretly just half a parabola. You can do away with the min/max wrapper if you just clamp the input to [0,100].

Is what you posted the officially used formula?