-38.05% is the change from 678 to 420
Calculation steps:
[( 420 - 678 ) ÷ 678] x 100 = -38.05%
Formula
Percentage change = [(420 - 678) / 678] x 100
Subtract the new number by the original number
420 - 678 = -258
-258 ÷ 678 = -0.3805309734513274
-0.3805309734513274 x 100 = -38.05%