condition mean min max ZT0-3 23.357985 23.357985 23.357985 ZT4-7 18.605823 18.605823 18.605823 ZT8-11 16.9764775 16.9764775 16.9764775 ZT12-15 16.774628 16.774628 16.774628 ZT16-19 17.8615955 17.8615955 17.8615955 ZT20-23 20.280627000000003 20.280627000000003 20.280627000000003