Basics
This is a custom stat, not listed in youtube studio. It's the average view duration, multiplied by the CTR.
Learn
Some people think this is the best stat to focus on. Many think it's absolutely useless, and if anything, misleading. We provide the calculation for you, but it's up to you to decide if it's useful or not. Here's a thread on where it might be useful: https://twitter.com/CharlesWeill/status/1535310836926922752 Here's a thread on where it might be misleading: https://twitter.com/wono_strategy/status/1607439670295810048
Gotchas
Many stats on YouTube can be misleading. This is multiplying two stats that are already hard to understand, so it's possible this is even more misleading. Do your research and decide how you feel about this stat. Filter out this stat if you don't find it useful.
Advanced
If you're big, just focus on views. You probably don't need this number.