condition mean min max ZT0-3 4.9706600000000005 4.9706600000000005 4.9706600000000005 ZT4-7 4.91719 4.91719 4.91719 ZT8-11 5.277865 5.277865 5.277865 ZT12-15 4.58124 4.58124 4.58124 ZT16-19 6.913555000000001 6.913555000000001 6.913555000000001 ZT20-23 5.087815 5.087815 5.087815