20.9% is the change from 646 to 781
Calculation steps:
[( 781 - 646 ) ÷ 646] x 100 = 20.9%
Formula
Percentage change = [(781 - 646) / 646] x 100
Subtract the new number by the original number
781 - 646 = 135
135 ÷ 646 = 0.2089783281733746
0.2089783281733746 x 100 = 20.9%