condition mean min max ZT0-3 9.595659999999999 9.284405 9.906915 ZT4-7 6.98016 6.98016 6.98016 ZT8-11 8.424814999999999 8.424814999999999 8.424814999999999 ZT12-15 0 0 0 ZT16-19 7.941660000000001 7.941660000000001 7.941660000000001 ZT20-23 9.262599999999999 9.262599999999999 9.262599999999999