condition mean min max ZT0-3 237.327387 237.327387 237.327387 ZT4-7 421.15535950000003 421.15535950000003 421.15535950000003 ZT8-11 390.47252100000003 390.47252100000003 390.47252100000003 ZT12-15 296.9015635 296.9015635 296.9015635 ZT16-19 272.131123 272.131123 272.131123 ZT20-23 223.1280925 223.1280925 223.1280925