condition mean min max ZT0-3 4.491011666666666 2.61587 5.9168899999999995 ZT4-7 1.28003 1.28003 1.28003 ZT8-11 2.46617 2.46617 2.46617 ZT12-15 3.8826 3.42123 4.34397 ZT16-19 3.795955 3.795955 3.795955 ZT20-23 7.773465 7.773465 7.773465