How to refer to time duration on charts

The chart below has a total duration of one week, and the data was grouped by a one day duration to come up with each of the bars.

What should the total duration (1 week) and group by duration (1 day) be referred to as?

My purpose is I am building a little chart wizard. I ask the user to enter the full duration and the bar duration. I want to use terms which will be obvious to the user.