filtering by # of days before (todays date)

Is there a way in a macro to filter by # of days prior to todays date? in other words, I have a date column of when a pc last connected. I need to see all of the pc's that last connected before 45 days ago. anything 45 days is ok.

Manually I would go up to sort/filter, click filter and then the top row would change to where I can filter by date "before". I would have to calculate 45 days ago and then select the date and then it would filter out the pc's.

so is there a way to say this in macro?

thanks in advance!

Chris