Can you explain what you want to see in your chart in a bit more detail?
Do you want to see 12 points plotted (12 bars in a bar chart perhaps?) where each represents a single month of the year? (Or maybe a fiscal year?)
Given the large number of facilities, I don't think you want one point for each facility for each month so I don't understand why you are sorting by Facilities instead of just by monthYear.
PS. I use this calculation when I want to group dated records by month in chronological order:
DateField - Day ( DateField ) + 1
It returns the date of the first day of the month for all dates.
Reason i'm grouping by facilities is because it's a comparison, i need one facility by itself and the rest of the facilities together
Series 1: Facility X
Series 2: Averages for All Facilities
In what kind of chart? Bar Chart? Line Chart? or ???