condition mean min max ZT0-3 39.199999999999996 39.199999999999996 39.199999999999996 ZT4-7 29.2 29.2 29.2 ZT8-11 5.300000000000001 5.300000000000001 5.300000000000001 ZT12-15 28.349999999999998 28.349999999999998 28.349999999999998 ZT16-19 15.899999999999999 15.899999999999999 15.899999999999999 ZT20-23 10.8 10.8 10.8