condition mean min max ZT0-3 24.785192 24.785192 24.785192 ZT4-7 17.5820595 17.5820595 17.5820595 ZT8-11 22.2963355 22.2963355 22.2963355 ZT12-15 27.769184 27.769184 27.769184 ZT16-19 32.510459 32.510459 32.510459 ZT20-23 35.932503 35.932503 35.932503