-14.11% is the change from 978 to 840
Calculation steps:
[( 840 - 978 ) ÷ 978] x 100 = -14.11%
Formula
Percentage change = [(840 - 978) / 978] x 100
Subtract the new number by the original number
840 - 978 = -138
-138 ÷ 978 = -0.1411042944785276
-0.1411042944785276 x 100 = -14.11%