condition mean min max ZT0-3 25.376013892499998 22.611782405 28.14024538 ZT4-7 15.924987866750001 12.4894991635 19.360476570000003 ZT8-11 30.688839594999997 21.517573295 39.860105895 ZT12-15 28.2762896 23.37706655 33.17551265 ZT16-19 18.061357795 17.42901764 18.69369795 ZT20-23 21.84379189 20.573802065 23.113781715000002