condition mean min max ZT0-3 6.0610599999999994 5.894765 6.227354999999999 ZT4-7 4.00728 4.00728 4.00728 ZT8-11 5.50031 5.50031 5.50031 ZT12-15 0 0 0 ZT16-19 5.50911 5.50911 5.50911 ZT20-23 5.47597 5.47597 5.47597