condition mean min max ZT0-3 6.5606375 6.16657 6.954705 ZT4-7 5.010475 5.010475 5.010475 ZT8-11 6.59987 6.59987 6.59987 ZT12-15 0 0 0 ZT16-19 6.322895 6.322895 6.322895 ZT20-23 6.968705 6.968705 6.968705