condition mean min max ZT0-3 2183.906767 2183.906767 2183.906767 ZT4-7 1720.5702575 1720.5702575 1720.5702575 ZT8-11 1850.63599 1850.63599 1850.63599 ZT12-15 2229.915373 2229.915373 2229.915373 ZT16-19 3042.590682 3042.590682 3042.590682 ZT20-23 3721.794854 3721.794854 3721.794854