condition mean min max ZT0-3 1.129397 0.915633 1.343161 ZT4-7 0.59114 0.59114 0.59114 ZT8-11 0.673238 0.673238 0.673238 ZT12-15 0 0 0 ZT16-19 0.9126274999999999 0.9126274999999999 0.9126274999999999 ZT20-23 0.9951495 0.9951495 0.9951495