condition mean min max ZT0-3 12.552109999999999 3.20548 17.7061 ZT4-7 5.80848 5.80848 5.80848 ZT8-11 4.744815 4.744815 4.744815 ZT12-15 7.935194999999999 5.581465 10.288924999999999 ZT16-19 17.91545 17.91545 17.91545 ZT20-23 23.45315 23.45315 23.45315