condition mean min max ZT0-3 433.616672 433.616672 433.616672 ZT4-7 720.6750724999999 720.6750724999999 720.6750724999999 ZT8-11 738.980356 738.980356 738.980356 ZT12-15 633.4265215 633.4265215 633.4265215 ZT16-19 488.5744775 488.5744775 488.5744775 ZT20-23 468.4290585 468.4290585 468.4290585