-51.74% is the change from 661 to 319
Calculation steps:
[( 319 - 661 ) ÷ 661] x 100 = -51.74%
Formula
Percentage change = [(319 - 661) / 661] x 100
Subtract the new number by the original number
319 - 661 = -342
-342 ÷ 661 = -0.5173978819969742
-0.5173978819969742 x 100 = -51.74%