Here are YouTube CPM factor, (Based on asumption)

You can try follow this matters and try to find out yourself and so report here later. Or you can tell other factor then i will add to the list.

1. Face
2. Quantity of Published videos in your channel (higher better CPM)
3. Ad-breaks
4. View minutes (Higher better CPM if it touch ad-breaks)
5. Number of hits (lower better CPM)
6. Niches
7. Video variation
8. [Empty]
9. [Empty]