condition mean min max ZT0-3 0.40061396666666665 0.2698299 0.6619189999999999 ZT4-7 0.28917899999999996 0.28917899999999996 0.28917899999999996 ZT8-11 0.32973399999999997 0.32973399999999997 0.32973399999999997 ZT12-15 0.5433775000000001 0.46196000000000004 0.624795 ZT16-19 0.4835325 0.4835325 0.4835325 ZT20-23 0.580506 0.580506 0.580506