Hey Power BI aficionados
So I have data set that looks something like the below (this is not the complete data set):
| Date (Year/Month) | Incident | Incident Type |
| 2018/Oct | Inc 1 | Type 1 |
| 2018/Oct | Inc 2 | Type 2 |
| 2018/Nov | Inc 3 | Type 4 |
| 2018/Dec | Inc 4 | Type 7 |
| 2018/Dec | Inc 5 | Type 1 |
| 2018/Dec | Inc 6 | Type 3 |
| 2019/Jan | Inc 7 | Type 6 |
| 2019/Jan | Inc 8 | Type 2 |
What I'm trying calculate via DAX is the average of count of incidents per incident type per month. For Eg: Averge number of incidents for the incident type Type 6 between the period 2018/Oct and 2019/Jul is calculated in the below table as (1+3+4+2+2+2)/6 = 2.3 (each of the cell value in the below table corresponds to the count of incidents per incident type per month). I'd like to be able to calculate the average of count for last 'n' months, for instance if we were in Jan 2020 and I'd like the DAX to calculate last 10 months average (n = 10).
| Incident Type | 2018/Oct | 2018/Nov | 2018/Dec | 2019/Jan | 2019/Feb | 2019/Mar | 2019/Apr | 2019/May | 2019/Jun | 2019/Jul | Grand Total | Average |
| Type 1 | 2 | 2 | 2 | 4 | 3 | 3 | 3 | 3 | 4 | 1 | 27 | 2.7 |
| Type 2 | 5 | 2 | 1 | 1 | | 1 | 8 | 2 | 5 | 6 | 31 | 3.4 |
| Type 3 | 2 | 1 | | | 1 | 2 | 1 | | | | 7 | 1.4 |
| Type 4 | 10 | 4 | 4 | 10 | 8 | | 9 | 3 | 10 | 4 | 62 | 6.9 |
| Type 5 | | | | | | 3 | | | | | 3 | 3.0 |
| Type 6 | 1 | 3 | 4 | | | 2 | 2 | 2 | | | 14 | 2.3 |
| Type 7 | 5 | 12 | 5 | 6 | 4 | 4 | | 3 | 1 | 1 | 41 | 4.6 |
| Type 8 | 1 | 2 | 1 | 1 | | | 3 | 2 | 6 | 2 | 18 | 2.3 |
| Type 9 | | | 1 | | 1 | | | | | 2 | 4 | 1.3 |
| Type 10 | | 1 | 1 | 1 | | | | 1 | | | 4 | 1.0 |
| Total | 26 | 27 | 19 | 23 | 17 | 15 | 26 | 16 | 26 | 16 | 211 | 21.1 |
Please let me know if you'd like any more info or if any of this isn't clear.
Thanks in advance for your help.
Cheers
