condition mean min max ZT0-3 2.585925 2.585925 2.585925 ZT4-7 2.252215 2.252215 2.252215 ZT8-11 2.110525 2.110525 2.110525 ZT12-15 2.2343450000000002 2.2343450000000002 2.2343450000000002 ZT16-19 2.2347799999999998 2.2347799999999998 2.2347799999999998 ZT20-23 2.28917 2.28917 2.28917