condition mean min max ZT0-3 656.301509 656.301509 656.301509 ZT4-7 741.6384284999999 741.6384284999999 741.6384284999999 ZT8-11 666.068483 666.068483 666.068483 ZT12-15 549.3088435 549.3088435 549.3088435 ZT16-19 514.9788975 514.9788975 514.9788975 ZT20-23 599.638533 599.638533 599.638533