condition mean min max ZT0-3 0.6527983333333334 0.6527983333333334 0.6527983333333334 ZT4-7 0.50337 0.50337 0.50337 ZT8-11 0.6426065000000001 0.6426065000000001 0.6426065000000001 ZT12-15 1.0523285 1.0523285 1.0523285 ZT16-19 0.572985 0.572985 0.572985 ZT20-23 0.618467 0.618467 0.618467