condition mean min max ZT0-3 48.513800780000004 47.727797370000005 49.29980419 ZT4-7 38.965419860000004 38.837557985000004 39.093281735000005 ZT8-11 20.0667589985 15.425128862000001 24.708389135 ZT12-15 5.0424213922500005 4.9645313975 5.120311387 ZT16-19 10.468882791999999 8.889319618999998 12.048445964999999 ZT20-23 12.30097295 11.66624118 12.93570472