condition mean min max ZT0-3 3.676716666666666 2.90759 4.208349999999999 ZT4-7 3.17795 3.17795 3.17795 ZT8-11 3.27989 3.27989 3.27989 ZT12-15 4.6065925 4.17278 5.040405 ZT16-19 3.92368 3.92368 3.92368 ZT20-23 5.64148 5.64148 5.64148