It's is common the customer to request an easy way to compare two date ranges.
i.e: I select the current month, and want to compare with the previous month, or with the same month one year ago. And it can be the month, a selection containing some days, a weekday, a quarter, and so on.
It's pretty easy to do it on Google Analytics, as the image below
Does someone has a tip or some article or a step by step to how achieve this great funcionality?