30.12% is the change from 644 to 838
Calculation steps:
[( 838 - 644 ) ÷ 644] x 100 = 30.12%
Formula
Percentage change = [(838 - 644) / 644] x 100
Subtract the new number by the original number
838 - 644 = 194
194 ÷ 644 = 0.30124223602484473
0.30124223602484473 x 100 = 30.12%