condition mean min max ZT0-3 1.47904 1.4057300000000001 1.55235 ZT4-7 2.728725 2.728725 2.728725 ZT8-11 3.89752 3.89752 3.89752 ZT12-15 0 0 0 ZT16-19 3.2418899999999997 3.2418899999999997 3.2418899999999997 ZT20-23 3.016685 3.016685 3.016685