-15.85% is the change from 978 to 823
Calculation steps:
[( 823 - 978 ) ÷ 978] x 100 = -15.85%
Formula
Percentage change = [(823 - 978) / 978] x 100
Subtract the new number by the original number
823 - 978 = -155
-155 ÷ 978 = -0.15848670756646216
-0.15848670756646216 x 100 = -15.85%