-16.5% is the change from 612 to 511
Calculation steps:
[( 511 - 612 ) ÷ 612] x 100 = -16.5%
Formula
Percentage change = [(511 - 612) / 612] x 100
Subtract the new number by the original number
511 - 612 = -101
-101 ÷ 612 = -0.1650326797385621
-0.1650326797385621 x 100 = -16.5%