Conditional formatting of column in pivot table

All,

          I am relatively new to BI Publisher. I have a simple requirement - I want to be able to change the column format of all from number to 99.0% based on the value of the header.

For example, I have column headers, Q1-2001, Q2-2001 and Q/Q% where I am comapring 2 quarter values. I want to change format of column Q/Q% from default number to 99.0%.

I tried using this in the column properties -

<?if:substring(./H,1,3)='Q/Q'?> 

<?format-number:fieldname;'99.0%'?>

<?end if?>

<?./M1?>

This does not work. Any suggestions to get the syntax right would be great help.