using parameters in default formula for another parameter in Pentaho report Designer
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I have two parameters defined in a Pentaho Report, both of them are dates, end date is something the user picks for eg. 2012-07-09 (July 9th 2012). The other parameter(start date) is hidden and is supposed to be the end date-6 so that would be July 3rd 2012. Is there any way I can pass the end date to the start date parameter and use it in the Default Formula value. 

I would really appreciate if someone could help me with this.

Thanks in advance.