-78.31% is the change from 830 to 180
Calculation steps:
[( 180 - 830 ) ÷ 830] x 100 = -78.31%
Formula
Percentage change = [(180 - 830) / 830] x 100
Subtract the new number by the original number
180 - 830 = -650
-650 ÷ 830 = -0.7831325301204819
-0.7831325301204819 x 100 = -78.31%