condition mean min max ZT0-3 4.6686525 3.7375 5.599805 ZT4-7 3.209835 3.209835 3.209835 ZT8-11 2.8817 2.8817 2.8817 ZT12-15 0 0 0 ZT16-19 3.1109850000000003 3.1109850000000003 3.1109850000000003 ZT20-23 3.36627 3.36627 3.36627