-99.9% is the change from 971 to 1
Calculation steps:
[( 1 - 971 ) ÷ 971] x 100 = -99.9%
Formula
Percentage change = [(1 - 971) / 971] x 100
Subtract the new number by the original number
1 - 971 = -970
-970 ÷ 971 = -0.9989701338825953
-0.9989701338825953 x 100 = -99.9%