-51.47% is the change from 680 to 330
Calculation steps:
[( 330 - 680 ) ÷ 680] x 100 = -51.47%
Formula
Percentage change = [(330 - 680) / 680] x 100
Subtract the new number by the original number
330 - 680 = -350
-350 ÷ 680 = -0.5147058823529411
-0.5147058823529411 x 100 = -51.47%