condition mean min max ZT0-3 5.976752748499999 4.974285799 6.979219698 ZT4-7 7.73416004075 7.419954626499999 8.048365455 ZT8-11 9.72223348525 9.476633077999999 9.9678338925 ZT12-15 10.98035861 10.186043928 11.774673292 ZT16-19 11.4581729275 10.833875305 12.08247055 ZT20-23 8.457942854999999 7.523050736 9.392834974