-47.8% is the change from 820 to 428
Calculation steps:
[( 428 - 820 ) ÷ 820] x 100 = -47.8%
Formula
Percentage change = [(428 - 820) / 820] x 100
Subtract the new number by the original number
428 - 820 = -392
-392 ÷ 820 = -0.47804878048780486
-0.47804878048780486 x 100 = -47.8%