-57.53% is the change from 511 to 217
Calculation steps:
[( 217 - 511 ) ÷ 511] x 100 = -57.53%
Formula
Percentage change = [(217 - 511) / 511] x 100
Subtract the new number by the original number
217 - 511 = -294
-294 ÷ 511 = -0.5753424657534246
-0.5753424657534246 x 100 = -57.53%