condition mean min max ZT0-3 48.68301666666667 38.56115 54.9056 ZT4-7 27.5494 27.5494 27.5494 ZT8-11 20.461100000000002 20.461100000000002 20.461100000000002 ZT12-15 35.048775000000006 29.73095 40.366600000000005 ZT16-19 41.89965 41.89965 41.89965 ZT20-23 60.46085 60.46085 60.46085