Dashboard prompt for effective date reporting possible?

Summary:

Hi all,

I have added

SET VARIABLE PARAM_EFFECTIVE_DATE = '@{P_DATE}{@{system.currentTime}[YYYY-MM-DD]}';

into the advanced tab under prefix for a OTBI analysis on Subject area Worker Assignment Real time.

I have also added it as a prompt (presentation variable P_DATE) and all works great.

My question - Is it possible to pass this in a Dashboard prompt? rather than as a prompt as part of the analysis?

I ask as I will have several different analysis reports on a dashboard page (all based on the same above subject area) and would rather pass the effective date once using a dashboard prompt rather than having to enter against each analysis.