condition mean min max ZT0-3 1.8301273374999998 0.768722344 2.8915323309999996 ZT4-7 5.4380495705000005 4.861743089 6.014356052 ZT8-11 7.742568087 6.368632347 9.116503827 ZT12-15 9.8597523365 8.525699484333334 11.193805188666666 ZT16-19 10.721484547500001 10.460670685 10.98229841 ZT20-23 8.542576496 7.520486827 9.564666165