-78.77% is the change from 391 to 83
Calculation steps:
[( 83 - 391 ) ÷ 391] x 100 = -78.77%
Formula
Percentage change = [(83 - 391) / 391] x 100
Subtract the new number by the original number
83 - 391 = -308
-308 ÷ 391 = -0.7877237851662404
-0.7877237851662404 x 100 = -78.77%