Mini-mash efficiency?

I am using BeerAlchemy software to calculate recipes, and one of the fields in the "Processes" column is "Mash Efficiency."

As of now I am doing Partial Mash/ Steeping with extract, generally adding around 1lbs of 6-row pale malt to both my steeping extract grains, and to a separate pot where I have my malt extract. (I later combine the two and commence the boil.)

My question is (roughly) what percentage should I list as my mash efficiency, as this affects both the OG/FG and IBU calculations....

Thanks and cheers

anywhere between 65% and 75% is probably going to work, although it shouldn't be that significant being such a small percentage of the fermentables. The eff shouldn't affect your OG with respect to the extract. Also, are you mini-mashing or steeping? Steeping is generally used to derive color, flavor, and aroma from the grain and not intended to convert and pull a significant amount of sugars from the grain.