-99.89% is the change from 870 to 1
Calculation steps:
[( 1 - 870 ) ÷ 870] x 100 = -99.89%
Formula
Percentage change = [(1 - 870) / 870] x 100
Subtract the new number by the original number
1 - 870 = -869
-869 ÷ 870 = -0.9988505747126437
-0.9988505747126437 x 100 = -99.89%