Analytics to report on average calls per hour

We have an area that receives calls that are handled through a Call Queue. The manager of the area wants to look at average call volumes to manage appropriate staffing. So, they want to look back over a period of weeks (e.g. last 12 weeks) and see the average calls by weekday and time. (Sundays at 9 AM, 10 AM, 11 AM... Mondays at 9 AM, 10 AM, etc.) All of the analytics available make this unique by date, but we want to look at the AVERAGE over 12 weeks of Sundays at 9 AM. That will result in better data to analyze.