condition mean min max ZT0-3 8.154365 7.366625 8.942105 ZT4-7 4.055485 4.055485 4.055485 ZT8-11 2.7806699999999998 2.7806699999999998 2.7806699999999998 ZT12-15 0 0 0 ZT16-19 5.2839 5.2839 5.2839 ZT20-23 7.052490000000001 7.052490000000001 7.052490000000001