condition mean min max ZT0-3 180.834235 180.834235 180.834235 ZT4-7 638.6990639999999 638.6990639999999 638.6990639999999 ZT8-11 492.36450549999995 492.36450549999995 492.36450549999995 ZT12-15 390.85419149999996 390.85419149999996 390.85419149999996 ZT16-19 197.399786 197.399786 197.399786 ZT20-23 111.9444405 111.9444405 111.9444405