condition mean min max ZT0-3 6.66676580775 5.057690786499999 8.275840829 ZT4-7 5.8111027845 5.221684864 6.400520705 ZT8-11 5.94160548775 5.4223811595 6.460829816 ZT12-15 7.979259321 6.590436453000001 9.368082188999999 ZT16-19 10.180392037499999 8.7861242835 11.5746597915 ZT20-23 19.9709691425 16.033838505 23.90809978