condition mean min max ZT0-3 5.856411666666667 5.4583200000000005 6.33253 ZT4-7 1.64567 1.64567 1.64567 ZT8-11 2.417075 2.417075 2.417075 ZT12-15 4.69386 4.14673 5.24099 ZT16-19 4.379775 4.379775 4.379775 ZT20-23 6.191715 6.191715 6.191715