1540% is the change from 50 to 820
Calculation steps:
[( 820 - 50 ) ÷ 50] x 100 = 1540%
Formula
Percentage change = [(820 - 50) / 50] x 100
Subtract the new number by the original number
820 - 50 = 770
770 ÷ 50 = 15.4
15.4 x 100 = 1540%
Example