-49.52% is the change from 830 to 419
Calculation steps:
[( 419 - 830 ) ÷ 830] x 100 = -49.52%
Formula
Percentage change = [(419 - 830) / 830] x 100
Subtract the new number by the original number
419 - 830 = -411
-411 ÷ 830 = -0.4951807228915663
-0.4951807228915663 x 100 = -49.52%