condition mean min max ZT0-3 6.786427783000001 4.3313509 9.241504666 ZT4-7 9.670005267499999 8.941199014999999 10.398811519999999 ZT8-11 12.6273322875 11.182298424999999 14.07236615 ZT12-15 10.722094340999998 10.526334295 10.917854386999998 ZT16-19 13.844587265 11.98194564 15.70722889 ZT20-23 21.1880091675 20.325856514999998 22.05016182