-80.2% is the change from 409 to 81
Calculation steps:
[( 81 - 409 ) ÷ 409] x 100 = -80.2%
Formula
Percentage change = [(81 - 409) / 409] x 100
Subtract the new number by the original number
81 - 409 = -328
-328 ÷ 409 = -0.8019559902200489
-0.8019559902200489 x 100 = -80.2%