Ordering based on parameters

Hey all,

I have a report with a line graph where the x-axis is time and the y-axis is some averaged value. I want to have a parameter that allows people to easily change the 'print for each _____' property of the line graph. For example, if the user selected 'minute' than the averaged value would be printed for each minute, if he selected 'day', than the average value would be printed for each day, etc. I want to do this so that if one happens to be looking at data ranging over a greater period such as 1month+, then they could, for example, select 'day' so that the chart is more readable.

thanks:)