21.84% is the change from 664 to 809
Calculation steps:
[( 809 - 664 ) ÷ 664] x 100 = 21.84%
Formula
Percentage change = [(809 - 664) / 664] x 100
Subtract the new number by the original number
809 - 664 = 145
145 ÷ 664 = 0.2183734939759036
0.2183734939759036 x 100 = 21.84%