condition mean min max ZT0-3 9.69975 9.69975 9.69975 ZT4-7 5.388835 5.388835 5.388835 ZT8-11 3.0400234999999998 3.0400234999999998 3.0400234999999998 ZT12-15 4.443015 4.443015 4.443015 ZT16-19 6.654835 6.654835 6.654835 ZT20-23 3.3048849999999996 3.3048849999999996 3.3048849999999996