condition mean min max ZT0-3 6.315988737 5.662599749 6.969377725 ZT4-7 6.29273604425 5.62950528 6.9559668084999995 ZT8-11 4.6063052540000005 4.3880361985 4.8245743095 ZT12-15 3.11822894275 2.9767486525 3.259709233 ZT16-19 4.326907662250001 3.7262558290000003 4.927559495500001 ZT20-23 5.964716438 5.8659291855 6.0635036905