Getting current date in relational

[thegiff]

I have two prompts and each prompt allows you to select a number day. If I select 1 and 18 it will give me all of the days from the 1st-18th. Right now the prompts default to the 1st and 2nd. I need the second prompt to default to the current day and I am not quite sure how to do that using a relational table. I know how to do it in a cube but I am not using that for this report. Any help is greatly appreciated.