condition mean min max ZT0-3 6.6741 6.64687 6.7013300000000005 ZT4-7 5.809200000000001 5.809200000000001 5.809200000000001 ZT8-11 6.7092600000000004 6.7092600000000004 6.7092600000000004 ZT12-15 0 0 0 ZT16-19 11.198799999999999 11.198799999999999 11.198799999999999 ZT20-23 6.9767600000000005 6.9767600000000005 6.9767600000000005