condition mean min max ZT0-3 1.0064498333333334 0.642055 1.49334 ZT4-7 0.768793 0.768793 0.768793 ZT8-11 0.7567145 0.7567145 0.7567145 ZT12-15 1.391675 1.3057699999999999 1.4775800000000001 ZT16-19 1.1011570000000002 1.1011570000000002 1.1011570000000002 ZT20-23 1.277815 1.277815 1.277815