condition mean min max ZT0-3 16.0625882125 16.060348055 16.06482837 ZT4-7 4.961691610999999 4.093520486499999 5.8298627355 ZT8-11 1.95477308625 1.850648512 2.0588976605 ZT12-15 3.89203829 3.3580603965 4.4260161835 ZT16-19 6.058491905 5.801067486000001 6.315916324 ZT20-23 8.06906234325 7.875212654 8.2629120325