-66.09% is the change from 991 to 336
Calculation steps:
[( 336 - 991 ) ÷ 991] x 100 = -66.09%
Formula
Percentage change = [(336 - 991) / 991] x 100
Subtract the new number by the original number
336 - 991 = -655
-655 ÷ 991 = -0.6609485368314834
-0.6609485368314834 x 100 = -66.09%