condition mean min max ZT0-3 540.372932 540.372932 540.372932 ZT4-7 576.0129485 576.0129485 576.0129485 ZT8-11 638.3533945 638.3533945 638.3533945 ZT12-15 663.566988 663.566988 663.566988 ZT16-19 918.246325 918.246325 918.246325 ZT20-23 948.3098115 948.3098115 948.3098115