-51.48% is the change from 643 to 312
Calculation steps:
[( 312 - 643 ) ÷ 643] x 100 = -51.48%
Formula
Percentage change = [(312 - 643) / 643] x 100
Subtract the new number by the original number
312 - 643 = -331
-331 ÷ 643 = -0.5147744945567652
-0.5147744945567652 x 100 = -51.48%