condition mean min max ZT0-3 13.688377 13.688377 13.688377 ZT4-7 14.2474795 14.2474795 14.2474795 ZT8-11 14.031946000000001 14.031946000000001 14.031946000000001 ZT12-15 13.640542499999999 13.640542499999999 13.640542499999999 ZT16-19 13.3687725 13.3687725 13.3687725 ZT20-23 13.699998 13.699998 13.699998