Can someone explain SR xp to me?

Do the XP multipliers reset every 10 levels? Level 69 was REALLY slow but 70-75 has felt shorter than that one level…

How does this system work exactly?

Each successive SR level requires a larger amount of XP to be achieved. Every 10 levels or so (until around SR 100) the XP amount required is reset.

Check out this earlier post:
https://www.halowaypoint.com/en-us/forums/6e35355aecdf4fd0acdaee3cc4156fd4/topics/max-sr-total-xp-needed-and-it-s-rewards/92cc2c88-3e28-454e-9688-f2b56cc56823/posts