condition mean min max ZT0-3 16.2986 16.2986 16.2986 ZT4-7 8.786575 8.786575 8.786575 ZT8-11 11.81665 11.81665 11.81665 ZT12-15 17.2377 17.2377 17.2377 ZT16-19 20.90155 20.90155 20.90155 ZT20-23 20.0959 20.0959 20.0959