condition mean min max ZT0-3 11.223044 11.223044 11.223044 ZT4-7 10.8612165 10.8612165 10.8612165 ZT8-11 11.630190500000001 11.630190500000001 11.630190500000001 ZT12-15 10.9665465 10.9665465 10.9665465 ZT16-19 12.3296025 12.3296025 12.3296025 ZT20-23 12.328666 12.328666 12.328666