-50.48% is the change from 630 to 312
Calculation steps:
[( 312 - 630 ) ÷ 630] x 100 = -50.48%
Formula
Percentage change = [(312 - 630) / 630] x 100
Subtract the new number by the original number
312 - 630 = -318
-318 ÷ 630 = -0.5047619047619047
-0.5047619047619047 x 100 = -50.48%