condition mean min max ZT0-3 31.256564 31.256564 31.256564 ZT4-7 34.317795000000004 34.317795000000004 34.317795000000004 ZT8-11 45.9187075 45.9187075 45.9187075 ZT12-15 49.204701 49.204701 49.204701 ZT16-19 54.884150500000004 54.884150500000004 54.884150500000004 ZT20-23 37.0160365 37.0160365 37.0160365