-83.9% is the change from 497 to 80
Calculation steps:
[( 80 - 497 ) ÷ 497] x 100 = -83.9%
Formula
Percentage change = [(80 - 497) / 497] x 100
Subtract the new number by the original number
80 - 497 = -417
-417 ÷ 497 = -0.8390342052313883
-0.8390342052313883 x 100 = -83.9%