How can an advertiser calculate the view rate of a video campaign?
- By looking at the percentage of viewers who watched the video until the last quartile
- By dividing the number of views by the number of impressions
- By dividing the number of impressions by the number of clicks
- By dividing the number of clicks by the number of views
View rate shows you the number of views or engagements your video ad receives divided by the number of times your ad is shown (video and thumbnail impressions).
View rate is similar to click-through rate (CTR), but instead of measuring clicks, it counts people who viewed your video ad after seeing it on YouTube or the Display Network. It is calculated by dividing the number of views by the number of impressions.
Read more here: https://support.google.com/partners/answer/6293479