Assuming you are not in Monte Carlo mode, this is how I see it:

Regular assets rate of return (RoR) impacts all assets in "Assets and Saving" tab. This includes new assets that are placed in the regular assets category such as from special receipts or 401k/IRA withdrawals that are in excess of a given year's spending requirements or selling a house, etc.

The RoR for retirement accounts covers those assets.

The nominal RoR gets converted to the equivalent "real" RoR for calculations and reports. For example, if you have a 6% rate of return and 3% inflation, your "real" or inflation adjusted dollars grow by around 3% annually in "real" terms (actually 2.913%).

Best,
Brian

Yes, and furthermore, it calculates from Jan. 1 through the end of the year. So when starting out, you don't want to enter you May balance (for example) in those accounts balance areas. We enter nominal rates of return (since that's how we all normally think about interest earned) but it's all presented in today's dollars, current year dollars.

Yes, perhaps I was confused by the question. Brian is correct. It's what everyone would naturally assume about a reported nominal return except that that the reports adjust for inflation and show the return denominated in current year dollars. I guess the best way to get at the meaning is to do as Brian did and enter an amount in any of the fields under regular assets. You don't even need to run a report: you can look at "current year saving" in the tab you see there. It will show Real Asset income (i.e., inflation adjusted) which it further defines this way: (dividends, interest, and other income earned on regular assets).

If for tax purposes you need to indicate that some of this income is cap gains or dividends or long term cap gains/losses, there is a place to do that for regular assets in Assumptions under the Taxes tab.