-69.67% is the change from 511 to 155
Calculation steps:
[( 155 - 511 ) ÷ 511] x 100 = -69.67%
Formula
Percentage change = [(155 - 511) / 511] x 100
Subtract the new number by the original number
155 - 511 = -356
-356 ÷ 511 = -0.6966731898238747
-0.6966731898238747 x 100 = -69.67%