-40.81% is the change from 517 to 306
Calculation steps:
[( 306 - 517 ) ÷ 517] x 100 = -40.81%
Formula
Percentage change = [(306 - 517) / 517] x 100
Subtract the new number by the original number
306 - 517 = -211
-211 ÷ 517 = -0.4081237911025145
-0.4081237911025145 x 100 = -40.81%