condition mean min max ZT0-3 4.36409 1.933095 6.465635000000001 ZT4-7 1.05962 1.05962 1.05962 ZT8-11 7.80298 7.80298 7.80298 ZT12-15 9.446485 6.03688 12.85609 ZT16-19 3.799575 3.799575 3.799575 ZT20-23 3.56092 3.56092 3.56092