condition mean min max ZT0-3 19.708531 19.708531 19.708531 ZT4-7 19.746655999999998 19.746655999999998 19.746655999999998 ZT8-11 17.1143915 17.1143915 17.1143915 ZT12-15 19.095336 19.095336 19.095336 ZT16-19 15.4755925 15.4755925 15.4755925 ZT20-23 15.5171925 15.5171925 15.5171925