condition mean min max ZT0-3 6.391691302249999 5.753390802999999 7.0299918015 ZT4-7 9.35461290975 7.7285920245 10.980633795 ZT8-11 23.15315314 17.51329656 28.79300972 ZT12-15 42.133824395 37.585702395 46.681946395 ZT16-19 52.45919744 49.30310727 55.615287609999996 ZT20-23 40.92340383 38.52229481 43.324512850000005