39.6% is the change from 644 to 899
Calculation steps:
[( 899 - 644 ) ÷ 644] x 100 = 39.6%
Formula
Percentage change = [(899 - 644) / 644] x 100
Subtract the new number by the original number
899 - 644 = 255
255 ÷ 644 = 0.39596273291925466
0.39596273291925466 x 100 = 39.6%