date manipulation

hi: I am trying to write a statement that gives me the date that is y days from the current date and time. For example, The following statement works in a stored procedure: define x datetime year to second; let x = current year to second - interval(1) day to day; In the above case I specified "1" day as a parameter to the interval function. Now for my specific scenario, I would like to use a variable as th parameter to the interval function. I get a syntax error. Does anyone have ideas on how I can accomplish it within the stored procedure? Thanks in advance. Sanjay