condition mean min max ZT0-3 3.714235 3.5290600000000003 3.8994099999999996 ZT4-7 3.629015 3.629015 3.629015 ZT8-11 3.454045 3.454045 3.454045 ZT12-15 0 0 0 ZT16-19 4.20434 4.20434 4.20434 ZT20-23 3.890485 3.890485 3.890485