How do I have more identifying bits of information, but it's shared by more browsers?

>Within our dataset of several million visitors, only one in 4,955 browsers have the same fingerprint as yours.

>Currently, we estimate that your browser has a fingerprint that conveys 12.27 bits of identifying information.

I figured it would be more unique due to my running Tor Browser on a Mac - but I don't see how the math works out. Unless it actually has a count of machines with information identical to mine?