-23.64% is the change from 643 to 491
Calculation steps:
[( 491 - 643 ) ÷ 643] x 100 = -23.64%
Formula
Percentage change = [(491 - 643) / 643] x 100
Subtract the new number by the original number
491 - 643 = -152
-152 ÷ 643 = -0.2363919129082426
-0.2363919129082426 x 100 = -23.64%