The DJ Gunga Scale of Forgotten-ness

The “DJ Gunga Scale of Forgotten-ness” (patent not pending) is a numeric ranking of just how obscure a record might be.  Despite my training at a top research university, there is nothing scientific about this scale.

1 – If you missed this one you weren’t paying attention.
2 – Shows up on some “hits of the 19xxs” compilations, maybe played as a “forgotten oldie”, or perhaps your gramma sang it once to annoy you.
3 – Tickled the charts but didn’t make them laugh.
4 – Came and went faster than a mayfly, good luck finding it on Spotify.
5 – What dusty corner of Soulville did you find this one in?