condition mean min max ZT0-3 24.33815 20.238 28.4383 ZT4-7 30.1699 30.1699 30.1699 ZT8-11 36.03875 36.03875 36.03875 ZT12-15 0 0 0 ZT16-19 39.254850000000005 39.254850000000005 39.254850000000005 ZT20-23 32.917 32.917 32.917