-99.7% is the change from 338 to 1
Calculation steps:
[( 1 - 338 ) ÷ 338] x 100 = -99.7%
Formula
Percentage change = [(1 - 338) / 338] x 100
Subtract the new number by the original number
1 - 338 = -337
-337 ÷ 338 = -0.9970414201183432
-0.9970414201183432 x 100 = -99.7%