-57.51% is the change from 506 to 215
Calculation steps:
[( 215 - 506 ) ÷ 506] x 100 = -57.51%
Formula
Percentage change = [(215 - 506) / 506] x 100
Subtract the new number by the original number
215 - 506 = -291
-291 ÷ 506 = -0.575098814229249
-0.575098814229249 x 100 = -57.51%