-51.04% is the change from 670 to 328
Calculation steps:
[( 328 - 670 ) ÷ 670] x 100 = -51.04%
Formula
Percentage change = [(328 - 670) / 670] x 100
Subtract the new number by the original number
328 - 670 = -342
-342 ÷ 670 = -0.5104477611940299
-0.5104477611940299 x 100 = -51.04%