-30.71% is the change from 928 to 643
Calculation steps:
[( 643 - 928 ) ÷ 928] x 100 = -30.71%
Formula
Percentage change = [(643 - 928) / 928] x 100
Subtract the new number by the original number
643 - 928 = -285
-285 ÷ 928 = -0.30711206896551724
-0.30711206896551724 x 100 = -30.71%