condition mean min max ZT0-3 0.5137285 0.5137285 0.5137285 ZT4-7 0.388672 0.388672 0.388672 ZT8-11 0.34759399999999996 0.34759399999999996 0.34759399999999996 ZT12-15 0.2944745 0.2944745 0.2944745 ZT16-19 0.420211 0.420211 0.420211 ZT20-23 0.43069999999999997 0.43069999999999997 0.43069999999999997