Because not all impressions are created equal, we buy based on what we call the AMP Index and measure based on video-neutral metrics, like those you see through Google's Brand Lift tool. It's our way of solving for video neutrality and measuring for impact.
Search lift, for example, is a video neutral metric that Google is now offering across both YouTube and television as part of their Brand Lift reporting. Now, you can see how many people searched for your brand or product after they saw your ad on television or on YouTube. One metric across all video platforms.