Using a Dummy Variable

You could always use a row under the first row

So row 1 would be 1, 10 , 100 , 1000
and row 2 would be

=IF($A$5=1,A1*0.3,A1), =IF($A$5=1,B1*0.3,B1), =IF($A$5=1,C1*0.3,C1), =IF($A$5=1,D1*0.3,D1)

Where A5 would be your variable cell