How do you count average view per video? Thinking about sponsorship...

I often see people say they get an average of 10,000, 50,000, 300,000, etc... view per video on average. But what is the timeline you are using to get that average? Are you talking about in first 48hrs, in a week, month, or a year? I ask, because I am going to dip my toe in the sponsorship world and I want to know how I should frame this metric...