condition mean min max ZT0-3 2.382730852 1.5774311719999998 3.188030532 ZT4-7 4.52341431775 3.849253226 5.197575409500001 ZT8-11 8.22457966275 7.3738227295 9.075336596 ZT12-15 10.012510888249999 9.2106095975 10.814412179 ZT16-19 7.8479457324999995 7.0784537165 8.617437748499999 ZT20-23 11.182236749000001 10.468989818 11.89548368