condition mean min max ZT0-3 15.08125 12.3345 17.828 ZT4-7 10.196825 10.196825 10.196825 ZT8-11 8.380525 8.380525 8.380525 ZT12-15 0 0 0 ZT16-19 14.692250000000001 14.692250000000001 14.692250000000001 ZT20-23 15.25675 15.25675 15.25675