-84.5% is the change from 258 to 40
Calculation steps:
[( 40 - 258 ) ÷ 258] x 100 = -84.5%
Formula
Percentage change = [(40 - 258) / 258] x 100
Subtract the new number by the original number
40 - 258 = -218
-218 ÷ 258 = -0.8449612403100775
-0.8449612403100775 x 100 = -84.5%