How much caffeine in a coffee bean?

In percent by mass would be the best form of an answer.

Ever since I was a tyke, I’ve seen commercials for a certain brand of decaffeinated coffee. The commercials always trumpeted the fact that their coffee was 97% caffeine-free. But what does that mean, actually? Is 97% of the original caffeine load removed? Or does a coffee bean naturally have some significant percent of its mass in the form of caffeine, and after decaffeination, that percentage is down to 3%?

I’ve been meaning to ask this question for years, ever since I learned that 2% low fat milk is just like whole milk except with half the fat, not with 8% of the fat removed.

So, how much caffeine can one find in a single coffee bean?

Caffeine Content in beans and blends, percentage by weight.

(Source: Newsletter–Mountanos Bros. Coffee Co., San Francisco)

Brazil Bourbons 1.20%
Celebes Kalossi 1.22
Colombia Excelso 1.37
Colombia Supremo 1.37
Ethiopian Harrar-Moka 1.13
Guatemala Antigua 1.32
Indian Mysore 1.37
Jamaican Blue Mtn/Wallensford Estate 1.24
Java Estate Kuyumas 1.20
Kenya AA 1.36
Kona Extra Prime 1.32
Mexico Pluma Altura 1.17
Mocha Mattari (Yemen) 1.01
New Guinea 1.30
Panama Organic 1.34
Sumatra Mandheling-Lintong 1.30
Tanzania Peaberry 1.42
Zimbabwe 1.10

Colombia Supremo Dark 1.37%
Espresso Roast 1.32
French Roast 1.22
Vienna Roast 1.27
Mocha-Java 1.17

DECAFS–all @ .02% with Swiss Water Process

Hey, thank you very much for that comprehensive list. Now I can sleep at night.

And before, I meant to say 98%, not 8% Preview is my friend, preview is my friend, preview is my friend, pre…