-81.98% is the change from 921 to 166
Calculation steps:
[( 166 - 921 ) ÷ 921] x 100 = -81.98%
Formula
Percentage change = [(166 - 921) / 921] x 100
Subtract the new number by the original number
166 - 921 = -755
-755 ÷ 921 = -0.8197611292073833
-0.8197611292073833 x 100 = -81.98%