condition mean min max ZT0-3 16.388067 16.388067 16.388067 ZT4-7 15.0338925 15.0338925 15.0338925 ZT8-11 13.258225 13.258225 13.258225 ZT12-15 13.280116 13.280116 13.280116 ZT16-19 13.537997 13.537997 13.537997 ZT20-23 13.679553 13.679553 13.679553