condition mean min max ZT0-3 0.7208488333333333 0.38618149999999996 0.9277275 ZT4-7 1.0170474999999999 1.0170474999999999 1.0170474999999999 ZT8-11 0.75049 0.75049 0.75049 ZT12-15 1.979675 1.42062 2.53873 ZT16-19 0.852649 0.852649 0.852649 ZT20-23 0.6461385 0.6461385 0.6461385