condition mean min max ZT0-3 4.926965 4.926965 4.926965 ZT4-7 4.344545 4.344545 4.344545 ZT8-11 6.33558 6.33558 6.33558 ZT12-15 5.492455 5.492455 5.492455 ZT16-19 6.6334 6.6334 6.6334 ZT20-23 4.6377299999999995 4.6377299999999995 4.6377299999999995