If the size of your penis matches the size of the world average penis and your body height reflects the world average body height, then your Pendex would be 100, which is the world average Pendex (Penis-Index).
This value will change accordingly, as your body and/or penis sizes changes.
If your body size is smaller than the world average body size, and your penis is also smaller than the world average penis – you can still – even with a smaller penis – have a Pendex of 100 or more. That’s because the size of your penis is still relating to the size of your body.
The other way around, very tall guys, with a bigger Penis can have a world average Pendex of 100 or less.