condition mean min max ZT0-3 0.643398 0.643398 0.643398 ZT4-7 0.3872521666666667 0.3872521666666667 0.3872521666666667 ZT8-11 0.38802190000000003 0.38802190000000003 0.38802190000000003 ZT12-15 0.26856 0.26856 0.26856 ZT16-19 0.6304 0.6304 0.6304 ZT20-23 0.427537 0.427537 0.427537