condition mean min max ZT0-3 23.524964 23.524964 23.524964 ZT4-7 22.8484505 22.8484505 22.8484505 ZT8-11 28.402034 28.402034 28.402034 ZT12-15 21.9737465 21.9737465 21.9737465 ZT16-19 26.4154815 26.4154815 26.4154815 ZT20-23 22.119967000000003 22.119967000000003 22.119967000000003