Strange statistics ( stat.fallOneCm )

I added stat (/scoreboard objectives add fall stat.fallOneCm) and decided to check it out.
Value is added only when falling from 2.11 blocks and above.
1) A fall from 3 blocks adds 269 cm
2) 4 blocks — 335 cm
3) 5 blocks — 484 cm
4) 6 blocks — 569 cm
5) 7 blocks — 659 cm
I think it's strange