-17.09% is the change from 989 to 820
Calculation steps:
[( 820 - 989 ) ÷ 989] x 100 = -17.09%
Formula
Percentage change = [(820 - 989) / 989] x 100
Subtract the new number by the original number
820 - 989 = -169
-169 ÷ 989 = -0.17087967644084934
-0.17087967644084934 x 100 = -17.09%