-49.61% is the change from 643 to 324
Calculation steps:
[( 324 - 643 ) ÷ 643] x 100 = -49.61%
Formula
Percentage change = [(324 - 643) / 643] x 100
Subtract the new number by the original number
324 - 643 = -319
-319 ÷ 643 = -0.49611197511664074
-0.49611197511664074 x 100 = -49.61%