Keeping conditional formatting when sorting
 

I have a survey data file that I would like to apply conditional formatting.
Each survey question is represented on 4 rows - sample size, column %, row %
and index. I only want the conditional formatting to occur on the index
rows. I've tried to sort by the column that has the word Index in it, apply
the conditional formatting, and then re-sort to the original order. However,
the conditional formatting stays in the rows and does not travel with the
data. For analysis reasons, I cannot eliminate the other rows. I have over
20,000 rows - any idea how I can do this besides applying the conditional
formatting to each row individually? Thanks!