condition mean min max ZT0-3 1.25176839075 0.972749223 1.5307875584999997 ZT4-7 1.6509572695 1.2974511450000001 2.004463394 ZT8-11 2.4433365929999997 1.7708605215 3.1158126645 ZT12-15 3.5202577965 2.732511529 4.308004064 ZT16-19 3.88835458025 3.763038421 4.0136707395 ZT20-23 4.0101935015 3.9069257105000004 4.1134612925