-16.8% is the change from 643 to 535
Calculation steps:
[( 535 - 643 ) ÷ 643] x 100 = -16.8%
Formula
Percentage change = [(535 - 643) / 643] x 100
Subtract the new number by the original number
535 - 643 = -108
-108 ÷ 643 = -0.16796267496111975
-0.16796267496111975 x 100 = -16.8%