-36.98% is the change from 668 to 421
Calculation steps:
[( 421 - 668 ) ÷ 668] x 100 = -36.98%
Formula
Percentage change = [(421 - 668) / 668] x 100
Subtract the new number by the original number
421 - 668 = -247
-247 ÷ 668 = -0.36976047904191617
-0.36976047904191617 x 100 = -36.98%