condition mean min max ZT0-3 2.6692150000000003 2.6692150000000003 2.6692150000000003 ZT4-7 1.47362 1.47362 1.47362 ZT8-11 1.97669 1.97669 1.97669 ZT12-15 2.8173250000000003 2.8173250000000003 2.8173250000000003 ZT16-19 4.12262 4.12262 4.12262 ZT20-23 2.89733 2.89733 2.89733