-21.14% is the change from 648 to 511
Calculation steps:
[( 511 - 648 ) ÷ 648] x 100 = -21.14%
Formula
Percentage change = [(511 - 648) / 648] x 100
Subtract the new number by the original number
511 - 648 = -137
-137 ÷ 648 = -0.21141975308641975
-0.21141975308641975 x 100 = -21.14%