-84.91% is the change from 921 to 139
Calculation steps:
[( 139 - 921 ) ÷ 921] x 100 = -84.91%
Formula
Percentage change = [(139 - 921) / 921] x 100
Subtract the new number by the original number
139 - 921 = -782
-782 ÷ 921 = -0.8490770901194354
-0.8490770901194354 x 100 = -84.91%