condition mean min max ZT0-3 10.352453 10.352453 10.352453 ZT4-7 9.797333 9.797333 9.797333 ZT8-11 10.775594 10.775594 10.775594 ZT12-15 20.134259 20.134259 20.134259 ZT16-19 21.919925499999998 21.919925499999998 21.919925499999998 ZT20-23 51.832417 51.832417 51.832417