condition mean min max ZT0-3 9.427133333333334 7.30972 11.519950000000001 ZT4-7 7.782304999999999 7.782304999999999 7.782304999999999 ZT8-11 9.633365000000001 9.633365000000001 9.633365000000001 ZT12-15 11.881599999999999 11.111049999999999 12.652149999999999 ZT16-19 12.1274 12.1274 12.1274 ZT20-23 15.03355 15.03355 15.03355