-16.63% is the change from 421 to 351
Calculation steps:
[( 351 - 421 ) ÷ 421] x 100 = -16.63%
Formula
Percentage change = [(351 - 421) / 421] x 100
Subtract the new number by the original number
351 - 421 = -70
-70 ÷ 421 = -0.166270783847981
-0.166270783847981 x 100 = -16.63%