Mid-year disruptions in the financial markets can raise questions about how to include sudden market gains or losses in your MaxiFi plan. If there is a change in your current-year labor earnings, certainly you should go ahead and enter that change to your wages. If you receive an unexpected bonus in June, just add that to labor earnings if it involves FICA or create a Special Receipt if it's merely taxable at ordinary rates without FICA tax.
But in order to account for dramatic market activity, up or down, you can use either of the following two approaches to adjust for your updated expectation about a safe return assumption for the current year:
I. Change Beginning of the Year Balance
You can do a mid-year update on regular and retirement assets by estimating the end of year balances given where they are currently, divide that by 1 plus your annual rate of return, and then entering that as you adjusted beginning year balance.
II. Changing Return Rates
Use Settings & Assumptions to change the current year safe return expectations (for regular and/or retirement assets) to a percentage you think you will "for sure" earn for the entire year given your asset allocation and your speculation about current year nominal return by the end of the year (not year to date). Most plans default at 0% real return (e.g. 1.5% inflation and 1.5% nominal return). If at some point in the year you become confident that your "for sure" rate of return is now 7% or -12% you can change those return rates for regular and/or retirement assets in the current year and then use the change of return to set them back to the default 0% real return beginning next year. After setting the current-year return, use the checkbox options below that setting to indicate a change in that return assumption back to a normal, cautious return of 0% (or whatever safe real return you assume for the following and subsequent years).
Remember, the return rate you enter using the approach above is for the entire current year, not just year-to-date, and it's not an assumption about "market return" (which often refers to the DOW or S&P index) but rather your assumption is about your personal return based on your asset allocation which may be a much less negative (or more positive) return than 100% stocks would provide. Keep in mind the lessons of 2018 as well where the stock market was +12% on Oct 1 and -5% on Dec 31. In other words, keep in mind that even in October it's hard to know for sure how it's all going to shake out for the year. Corrections in the market can be dramatic but reversals can be just as dramatic as they were mid-year in 2020.
Practical Consequences
What is the value of more accurately representing your current-year return rate? At the beginning of the year we use a cautious assumption of 0% or perhaps 1% real return as is appropriate for a deterministic model that bills itself as a safe, risk- free model. See Two Approaches and Two Purposes to Planning (why be so cautious?)
But late in the year, we might become more confident about what we can assume is a safe return for the current year. (But remember, things can change quickly, even in the final month of the year.) If we end up believing that say 6% will be a safe assumption in late October and enter that amount using the approach described above, we might discover that our annual discretionary spending has risen 2% for example, say from 90,000 annually to 91,800. Will you thus go out and spend an extra $1,800 before the end of the year? Maybe, but many users do not spend right at the safe, available margin. If this user's discretionary spending allowance is $90,000 but the user routinely under spends at say, $80,000, then knowing there is an extra $1,800, that is, $91,800, is not going to make any actionable difference and such a user might just as well wait until the end of the year to update balance since no real change is impacted by this late-year anticipation of what will count as a safe annual return assumption.