-89.9% is the change from 921 to 93
Calculation steps:
[( 93 - 921 ) ÷ 921] x 100 = -89.9%
Formula
Percentage change = [(93 - 921) / 921] x 100
Subtract the new number by the original number
93 - 921 = -828
-828 ÷ 921 = -0.8990228013029316
-0.8990228013029316 x 100 = -89.9%