With a domain like "Account Size" ...it doesn't hit me as meaning anything. Account size of what? If people have a bronze (or entry level), silver, gold, platinum account with a certain service - Makes sense, relates to different privileges, and so on. Even then, it wouldn't be considered the "size" of an account, it would be the "status", "level" or "upgrade" (but, that wouldn't be the domain name, the main business itself would be the domain)
I struggle, unless I'm missing something. I consider it little value, sadly