condition mean min max ZT0-3 56.634697 56.634697 56.634697 ZT4-7 51.759837 51.759837 51.759837 ZT8-11 46.252638 46.252638 46.252638 ZT12-15 49.766919 49.766919 49.766919 ZT16-19 50.6680075 50.6680075 50.6680075 ZT20-23 61.569121 61.569121 61.569121