condition mean min max ZT0-3 15.616481505 15.4422515 15.79071151 ZT4-7 9.490580673 8.9733158645 10.007845481499999 ZT8-11 9.508174936500001 8.295324128 10.721025745 ZT12-15 5.99274679925 4.472372857 7.5131207415 ZT16-19 4.097806073 3.8859891485 4.3096229975 ZT20-23 4.24838300125 3.9050449560000002 4.5917210465