condition mean min max ZT0-3 20.391728 20.391728 20.391728 ZT4-7 24.5902885 24.5902885 24.5902885 ZT8-11 24.528177 24.528177 24.528177 ZT12-15 20.733051000000003 20.733051000000003 20.733051000000003 ZT16-19 24.61749 24.61749 24.61749 ZT20-23 25.76268 25.76268 25.76268