condition mean min max ZT0-3 10.259914476999999 8.712977774 11.806851179999999 ZT4-7 8.215227439833333 7.547617879666666 8.882837 ZT8-11 11.911386722500001 9.944676141666667 13.878097303333334 ZT12-15 9.394424516499999 7.089055796333334 11.699793236666666 ZT16-19 5.179241134 4.801524259000001 5.556958009 ZT20-23 4.652744896166666 4.539176887 4.766312905333334