-50.08% is the change from 647 to 323
Calculation steps:
[( 323 - 647 ) ÷ 647] x 100 = -50.08%
Formula
Percentage change = [(323 - 647) / 647] x 100
Subtract the new number by the original number
323 - 647 = -324
-324 ÷ 647 = -0.500772797527048
-0.500772797527048 x 100 = -50.08%