condition mean min max ZT0-3 17.852337 17.852337 17.852337 ZT4-7 14.963085 14.963085 14.963085 ZT8-11 12.555731000000002 12.555731000000002 12.555731000000002 ZT12-15 14.4750665 14.4750665 14.4750665 ZT16-19 12.2061685 12.2061685 12.2061685 ZT20-23 10.8742045 10.8742045 10.8742045