-77.1% is the change from 939 to 215
Calculation steps:
[( 215 - 939 ) ÷ 939] x 100 = -77.1%
Formula
Percentage change = [(215 - 939) / 939] x 100
Subtract the new number by the original number
215 - 939 = -724
-724 ÷ 939 = -0.7710330138445154
-0.7710330138445154 x 100 = -77.1%