I noticed the tight grouping as well. I'm in the very low end...of the job level below me.
Did you receiver refreshers? Your stock growth alone should push you into upper bands if you stayed long.
Stock growth did result in a higher than expected TC, but the number of shares I have vesting will drop substantially over the next 2-3 years. If you're curious, every year I've been here my manager has given me great annual reviews. My base pay is substantially lower than the others on the list.
What are refreshers? Perhaps it's something I know by another term?
Btw, which office you’re in can make a gigantic difference. Amazon employees in India make a LOT less than in Seattle, for example.