condition mean min max ZT0-3 1.9542675000000003 1.8913250000000001 2.0172100000000004 ZT4-7 2.66768 2.66768 2.66768 ZT8-11 2.848935 2.848935 2.848935 ZT12-15 0 0 0 ZT16-19 2.88516 2.88516 2.88516 ZT20-23 2.1737450000000003 2.1737450000000003 2.1737450000000003