condition mean min max ZT0-3 16.809794 16.809794 16.809794 ZT4-7 14.896315 14.896315 14.896315 ZT8-11 17.7206705 17.7206705 17.7206705 ZT12-15 12.391249 12.391249 12.391249 ZT16-19 12.6218545 12.6218545 12.6218545 ZT20-23 13.409779 13.409779 13.409779