condition mean min max ZT0-3 21.1717 21.1717 21.1717 ZT4-7 17.51045 17.51045 17.51045 ZT8-11 16.31665 16.31665 16.31665 ZT12-15 16.35555 16.35555 16.35555 ZT16-19 32.645849999999996 32.645849999999996 32.645849999999996 ZT20-23 21.37905 21.37905 21.37905