condition mean min max ZT0-3 2.11912178125 0.6802442120000001 3.5579993505000003 ZT4-7 9.73980940125 6.7158568525 12.76376195 ZT8-11 15.6725377025 13.33016773 18.014907675 ZT12-15 21.0703344125 18.558870485 23.58179834 ZT16-19 20.4207501775 18.220175495 22.62132486 ZT20-23 27.5939777275 26.06558638 29.122369075