condition mean min max ZT0-3 325.261724 325.261724 325.261724 ZT4-7 451.351719 451.351719 451.351719 ZT8-11 497.086045 497.086045 497.086045 ZT12-15 446.2561885 446.2561885 446.2561885 ZT16-19 442.44579550000003 442.44579550000003 442.44579550000003 ZT20-23 415.0807365 415.0807365 415.0807365