33.5% is the change from 615 to 821
Calculation steps:
[( 821 - 615 ) ÷ 615] x 100 = 33.5%
Formula
Percentage change = [(821 - 615) / 615] x 100
Subtract the new number by the original number
821 - 615 = 206
206 ÷ 615 = 0.33495934959349594
0.33495934959349594 x 100 = 33.5%