condition mean min max ZT0-3 21.924500000000002 21.924500000000002 21.924500000000002 ZT4-7 18.671100000000003 18.671100000000003 18.671100000000003 ZT8-11 13.902000000000001 13.902000000000001 13.902000000000001 ZT12-15 15.42315 15.42315 15.42315 ZT16-19 17.3462 17.3462 17.3462 ZT20-23 24.89085 24.89085 24.89085