condition mean min max ZT0-3 1.593229 1.593229 1.593229 ZT4-7 1.1645919999999998 1.1645919999999998 1.1645919999999998 ZT8-11 0.7945325 0.7945325 0.7945325 ZT12-15 0.7147095 0.7147095 0.7147095 ZT16-19 0.573709 0.573709 0.573709 ZT20-23 2.15363 2.15363 2.15363