condition mean min max ZT0-3 15.84235 15.8351 15.849599999999999 ZT4-7 14.9281 14.9281 14.9281 ZT8-11 16.5492 16.5492 16.5492 ZT12-15 0 0 0 ZT16-19 17.211199999999998 17.211199999999998 17.211199999999998 ZT20-23 15.583400000000001 15.583400000000001 15.583400000000001