-68.49% is the change from 511 to 161
Calculation steps:
[( 161 - 511 ) ÷ 511] x 100 = -68.49%
Formula
Percentage change = [(161 - 511) / 511] x 100
Subtract the new number by the original number
161 - 511 = -350
-350 ÷ 511 = -0.684931506849315
-0.684931506849315 x 100 = -68.49%