condition mean min max ZT0-3 1985.304587 1985.304587 1985.304587 ZT4-7 1550.173791 1550.173791 1550.173791 ZT8-11 1632.9860250000002 1632.9860250000002 1632.9860250000002 ZT12-15 1467.3843495 1467.3843495 1467.3843495 ZT16-19 1286.214575 1286.214575 1286.214575 ZT20-23 1400.0127845000002 1400.0127845000002 1400.0127845000002