condition mean min max ZT0-3 3.9649500000000004 3.2324 4.448545 ZT4-7 3.24317 3.24317 3.24317 ZT8-11 5.94386 5.94386 5.94386 ZT12-15 10.825622500000001 8.191145 13.4601 ZT16-19 8.717130000000001 8.717130000000001 8.717130000000001 ZT20-23 5.804215 5.804215 5.804215