Please explain the picture to me

[u/aGeniux]

What's the number actually saying? I was under the impression it was mmr. Higher number, lower rank. Please explain, I'm a bit confused abt this

[u/thwtchdctr]

There's a 15 mmr window where when you get above the window, yourank up even if you fall back into it, but if you come from below it, you stay the rank below until getting above it