-69.12% is the change from 991 to 306
Calculation steps:
[( 306 - 991 ) ÷ 991] x 100 = -69.12%
Formula
Percentage change = [(306 - 991) / 991] x 100
Subtract the new number by the original number
306 - 991 = -685
-685 ÷ 991 = -0.6912209889001009
-0.6912209889001009 x 100 = -69.12%