condition mean min max ZT0-3 11.396666 11.396666 11.396666 ZT4-7 12.052050000000001 12.052050000000001 12.052050000000001 ZT8-11 12.4707595 12.4707595 12.4707595 ZT12-15 10.8112825 10.8112825 10.8112825 ZT16-19 11.5661815 11.5661815 11.5661815 ZT20-23 12.909965499999998 12.909965499999998 12.909965499999998