What it means
At an FOMC meeting, Federal Reserve officials review economic and financial conditions and decide whether to change US monetary policy. FOMC stands for Federal Open Market Committee. A closely watched outcome is the target range for the federal funds rate, the overnight rate at which banks lend reserve balances to one another.
The policy announcement can affect expectations for borrowing costs and the economy. Stocks may react not only to a rate decision but also to the accompanying statement and, when issued, economic projections. A market reaction depends on how the news compares with what investors had expected; an unchanged rate does not necessarily mean an unchanged outlook.
How it is calculated
An FOMC meeting is an event, not a calculated indicator. One number reported after a meeting is the federal funds target range. Its width can be calculated as range width (percentage points) = upper bound (%) − lower bound (%), where the upper bound and lower bound are the two announced target rates, each expressed as an annual percentage rate. A percentage-point difference is not a percentage change.
To describe a change from one meeting to another, use change in lower bound (basis points) = [new lower bound (%) − previous lower bound (%)] × 100. The new and previous lower bounds are the announced lower limits at the respective meetings. One basis point equals 0.01 percentage point. The same calculation can be made for the upper bound. These arithmetic descriptions do not measure the meeting’s effect on a stock price.
Worked example
Suppose, hypothetically, that before a meeting the target range is 4.00%–4.25%, and afterward it is 4.25%–4.50%.
- The old range width is
4.25% − 4.00% = 0.25 percentage point, or 25 basis points. - The new range width is
4.50% − 4.25% = 0.25 percentage point, also 25 basis points. - The lower bound rises from 4.00% to 4.25%:
0.25 × 100 = 25 basis points. The upper bound also rises by 25 basis points.
This describes a hypothetical 25-basis-point increase in the target range. It does not establish how much any stock will move. If investors expected the change, other parts of the announcement could matter more to the immediate market reaction.
Why it matters before you trade
An FOMC announcement is scheduled event risk for US stocks. Around the announcement, prices can move quickly, displayed quotes can change, and the price at which an order fills may differ from an earlier quote. These possibilities matter when considering order size, execution conditions, potential spread costs and whether a basket has substantial exposure to the same market-wide event.
A pre-trade check can separate what is known—such as the scheduled event and the basket’s size—from what remains uncertain, including the announcement’s content and the market response. A limit price controls the worst price acceptable for an order, but it does not guarantee a fill. Historical volatility and a one-day risk estimate also cannot guarantee a bound on losses during an event.
How PreTrAIde uses it
The product facts do not state that PreTrAIde tracks FOMC meetings or explicitly models their announcements. PreTrAIde provides pre-trade analysis for a user-built stock basket before the user places an order. Its analysis includes estimated spreads, participation in daily volume, market impact, daily volatility and one-day 95% value at risk, alongside recent news per ticker and analyst ratings.
Those measures can help describe execution conditions and risk for a proposed basket, but they should not be read as a prediction of an FOMC decision or its effect. PreTrAIde’s GO, NO-GO and MODIFY verdicts are decision support, not recommendations; users place any trades themselves through their own broker.
Common mistakes
- Treating a rate change as a stock-price forecast. The decision and the market’s expectations are different things.
- Confusing basis points with percent. A move from 4.00% to 4.25% is 25 basis points, not a 25% increase.
- Assuming an unchanged target range means no event risk. Wording or projections may still affect expectations.
- Treating a risk estimate as a guaranteed loss limit. Rapid moves and changing liquidity can make realized outcomes different from model estimates.