condition mean min max ZT0-3 3.312265 3.312265 3.312265 ZT4-7 2.90039 2.90039 2.90039 ZT8-11 3.129425 3.129425 3.129425 ZT12-15 2.873105 2.873105 2.873105 ZT16-19 2.366885 2.366885 2.366885 ZT20-23 1.9148900000000002 1.9148900000000002 1.9148900000000002