condition mean min max ZT0-3 16.5798275 13.172005 19.987650000000002 ZT4-7 8.37673 8.37673 8.37673 ZT8-11 7.29758 7.29758 7.29758 ZT12-15 0 0 0 ZT16-19 9.2554 9.2554 9.2554 ZT20-23 10.528680000000001 10.528680000000001 10.528680000000001