condition mean min max ZT0-3 23.598682778 15.802565216000001 31.39480034 ZT4-7 8.68474482375 7.137253257499999 10.23223639 ZT8-11 16.003881287 11.972989574 20.034773 ZT12-15 40.602743175 34.795636765 46.409849585 ZT16-19 68.49925504500001 62.49060181 74.50790828000001 ZT20-23 69.26947511750001 68.4350589 70.103891335