condition mean min max ZT0-3 1.7519175 1.631335 1.8725 ZT4-7 1.5162849999999999 1.5162849999999999 1.5162849999999999 ZT8-11 2.0514900000000003 2.0514900000000003 2.0514900000000003 ZT12-15 0 0 0 ZT16-19 2.45919 2.45919 2.45919 ZT20-23 2.4128800000000004 2.4128800000000004 2.4128800000000004