why lucas browne has a higher ko ratio than keith thurman?

[sam1988]

lucas browne has 20 fights 18 ko's and a 90% ko percent.

keith thurman has 23 fights and 21 kos and has ko percentage at 87.5% on boxrec?
keith thurman should have over 90% ko ratio, more than lucas browne.

mistake on boxrec.

[Freiheit]

Thurmann has had 24 fights, 23 wins and a ND