condition mean min max ZT0-3 445.497268 445.497268 445.497268 ZT4-7 514.657726 514.657726 514.657726 ZT8-11 646.282281 646.282281 646.282281 ZT12-15 564.4479045 564.4479045 564.4479045 ZT16-19 666.4959690000001 666.4959690000001 666.4959690000001 ZT20-23 581.6755995 581.6755995 581.6755995