-28.65% is the change from 939 to 670
Calculation steps:
[( 670 - 939 ) ÷ 939] x 100 = -28.65%
Formula
Percentage change = [(670 - 939) / 939] x 100
Subtract the new number by the original number
670 - 939 = -269
-269 ÷ 939 = -0.28647497337593186
-0.28647497337593186 x 100 = -28.65%