condition mean min max ZT0-3 6.9317025 6.85103 7.012375 ZT4-7 4.5608699999999995 4.5608699999999995 4.5608699999999995 ZT8-11 3.9585549999999996 3.9585549999999996 3.9585549999999996 ZT12-15 0 0 0 ZT16-19 5.15459 5.15459 5.15459 ZT20-23 7.008240000000001 7.008240000000001 7.008240000000001