Custom View time settings

Custom View time settings

I'd like to create a custom view (in invoices) that allows me to have a custom view showing invoices created in the last 7 days.  Could you tell me is there a Boolean phrase that would allow me to enter "last 7 days" or something like that? I'm using "created time" as the critieria, but can't find a way (or don't know the boolean phrase) to specify the last week.  Thanks for your help.