For a start, half of US adults are married, so aren't dating anyone at the moment. So that by itself seems to prove it right off the bat.

But beyond that, half of US adults are over 38, so likely many of these aren't dating even if they aren't married.

So seems obvious that fewer than half of US adults are dating at all, and obviously the only a proportion of that group will have also been dating ten years ago, as they won't be that old, or will have been previously married.

So how can half of all adults have an informed opinion on this?