26.95% is the change from 642 to 815
Calculation steps:
[( 815 - 642 ) ÷ 642] x 100 = 26.95%
Formula
Percentage change = [(815 - 642) / 642] x 100
Subtract the new number by the original number
815 - 642 = 173
173 ÷ 642 = 0.26947040498442365
0.26947040498442365 x 100 = 26.95%