condition mean min max ZT0-3 3.6436224999999998 3.2981049999999996 3.98914 ZT4-7 3.2468049999999997 3.2468049999999997 3.2468049999999997 ZT8-11 4.84244 4.84244 4.84244 ZT12-15 0 0 0 ZT16-19 9.830345 9.830345 9.830345 ZT20-23 6.095955 6.095955 6.095955