-86.1% is the change from 921 to 128
Calculation steps:
[( 128 - 921 ) ÷ 921] x 100 = -86.1%
Formula
Percentage change = [(128 - 921) / 921] x 100
Subtract the new number by the original number
128 - 921 = -793
-793 ÷ 921 = -0.8610206297502715
-0.8610206297502715 x 100 = -86.1%