-30.11% is the change from 920 to 643
Calculation steps:
[( 643 - 920 ) ÷ 920] x 100 = -30.11%
Formula
Percentage change = [(643 - 920) / 920] x 100
Subtract the new number by the original number
643 - 920 = -277
-277 ÷ 920 = -0.3010869565217391
-0.3010869565217391 x 100 = -30.11%