-66.12% is the change from 921 to 312
Calculation steps:
[( 312 - 921 ) ÷ 921] x 100 = -66.12%
Formula
Percentage change = [(312 - 921) / 921] x 100
Subtract the new number by the original number
312 - 921 = -609
-609 ÷ 921 = -0.6612377850162866
-0.6612377850162866 x 100 = -66.12%