condition mean min max ZT0-3 7.319004289499999 2.2460578819999997 12.391950696999999 ZT4-7 20.940007585 18.226997824999998 23.653017345000002 ZT8-11 15.08851951025 13.258870285500002 16.918168735 ZT12-15 8.207444421249999 8.1816064545 8.233282388 ZT16-19 13.938308222499998 11.92938485 15.947231594999998 ZT20-23 15.47013705 14.381643555 16.558630545