-53.1% is the change from 661 to 310
Calculation steps:
[( 310 - 661 ) ÷ 661] x 100 = -53.1%
Formula
Percentage change = [(310 - 661) / 661] x 100
Subtract the new number by the original number
310 - 661 = -351
-351 ÷ 661 = -0.5310136157337367
-0.5310136157337367 x 100 = -53.1%