-91.92% is the change from 421 to 34
Calculation steps:
[( 34 - 421 ) ÷ 421] x 100 = -91.92%
Formula
Percentage change = [(34 - 421) / 421] x 100
Subtract the new number by the original number
34 - 421 = -387
-387 ÷ 421 = -0.9192399049881235
-0.9192399049881235 x 100 = -91.92%