-37.18% is the change from 511 to 321
Calculation steps:
[( 321 - 511 ) ÷ 511] x 100 = -37.18%
Formula
Percentage change = [(321 - 511) / 511] x 100
Subtract the new number by the original number
321 - 511 = -190
-190 ÷ 511 = -0.37181996086105673
-0.37181996086105673 x 100 = -37.18%