condition mean min max ZT0-3 4.730120614750001 3.1835429110000004 6.276698318500001 ZT4-7 12.6194297 11.03077166 14.20808774 ZT8-11 16.150693079 13.651701348 18.649684809999997 ZT12-15 18.4450141625 17.74808265 19.141945675 ZT16-19 14.1839403175 13.664195565 14.70368507 ZT20-23 12.84092815525 10.494979410500001 15.186876899999998