condition mean min max ZT0-3 2.8128450000000003 2.75274 2.87295 ZT4-7 2.079205 2.079205 2.079205 ZT8-11 2.7129000000000003 2.7129000000000003 2.7129000000000003 ZT12-15 0 0 0 ZT16-19 2.65462 2.65462 2.65462 ZT20-23 3.440415 3.440415 3.440415