-34.56% is the change from 981 to 642
Calculation steps:
[( 642 - 981 ) ÷ 981] x 100 = -34.56%
Formula
Percentage change = [(642 - 981) / 981] x 100
Subtract the new number by the original number
642 - 981 = -339
-339 ÷ 981 = -0.345565749235474
-0.345565749235474 x 100 = -34.56%