Was ist der Pre-FOMC-Drift?

Als Pre-FOMC-Drift bezeichnet man die in einigen Studien beobachtete Tendenz von US-Aktien, in den Stunden und Tagen vor einer Fed-Entscheidung (t0) leicht zuzulegen. Das Event-Window-Tool macht solche Vorlauf-Muster sichtbar: Steigt die Durchschnittskurve bereits links von t0 an, war im gewählten Zeitraum ein Vorlauf-Effekt vorhanden. Ob er auch künftig auftritt, lässt sich daraus nicht ableiten.

Warum ist t0 der zweite Sitzungstag?

Fed (FOMC), EZB und einige andere Notenbanken tagen über zwei Tage. Die Zinsentscheidung wird erst am zweiten Tag veröffentlicht — dieser Tag der Bekanntgabe ist der Entscheidungstag und damit t0. Fällt der Termin auf einen Feiertag oder ein Wochenende, nutzt das Tool den nächsten Handelstag als Bezugspunkt.

Welche Notenbanken deckt das Tool ab?

Das Tool führt Sitzungstermine für Fed (FOMC), EZB, Bank of England, Bank of Japan, SNB, Bank of Canada, RBA und RBNZ. Die Marktreaktions-Analyse mit Event-Window-Chart steht aktuell für Fed, EZB, BoE und BoJ zur Verfügung — inklusive der Fed-Sonderfilter für Zinserhöhungen und Zinssenkungen. Welche Notenbank für einen Ticker relevant ist, richtet sich nach dem Handelsplatz bzw. der Währung.

Central Bank Effect — ^GSPC

Market reaction around central bank meetings (t0 = decision day)

Polymarket Fed Path 2026 — what the market is pricing in

Alongside the historical event analysis above: the implied probability distribution from the Polymarket event "How many Fed rate cuts in 2026?". 13 outcome markets (0, 1, 2, ... 12+ cuts), live via Polymarket API, weighted expected value as green line.

→ Full Polymarket page with history and risk markets

Methodology

Data Basis

Fed (FOMC): 224 meeting dates (2000–2026)
Fed rate hikes: 40 hike decisions (2000–2024) — only sessions at which the Fed raised the key rate
Fed rate cuts: 31 cut decisions (2000–2024) — only sessions at which the Fed lowered the key rate
ECB: 96 governing council meetings (2015–2026)
Bank of England: 58 MPC meetings (2020–2026)
Bank of Japan: 40 meetings (2022–2026)
Price data: Supabase (Yahoo Finance), updated daily

Hike vs. Cut Analysis

The Fed Rate Hikes and Fed Rate Cuts options let you analyze how the market reacts to the direction of the monetary policy decision — rather than all meetings indiscriminately. Classic thesis: equities rise after rate cuts (expansionary policy), fall after hikes (restrictive). A backtest shows whether this holds.

Calculation

t0: central bank decision day (or next trading day)
Normalisation: price path normalised to t0 = 0%
Window: t−N to t+N trading days around the decision day
Average curve: mean across all events in the period
Win Rate: share of events with positive return (t−N to t+N)

Understanding Central Bank Meetings — Dates, Market Reaction & Methodology

SeasonAlpha's Central Banks tool combines two things: a calendar of the key central bank meeting dates — Fed (FOMC), ECB, Bank of England (BoE), Bank of Japan (BoJ), SNB, BoC, RBA and RBNZ — and an analysis of how a market has historically behaved around those dates. You pick a ticker (e.g. the S&P 500) and a central bank; the tool overlays every past meeting and shows the average price move in the window around the decision day. This reveals whether a recurring pattern existed around monetary policy decisions — such as the well-known pre-FOMC drift, a slight upward tendency in the hours and days before the Fed decision.

The central reference point is t0, the decision day of the respective central bank. For two-day meetings — like the FOMC or the ECB — this is always the second day, when the decision is announced. In the event-window chart, t0 sits in the centre; to its left are the trading days before the meeting (t−1, t−2, …), to its right the days after (t+1, t+2, …). The average curve is the mean across all meetings in the selected period. If it rises before t0, that points to a run-up effect; a jump right after t0 shows the immediate market reaction to the decision. The sliders set the window (e.g. five days before and after t0); win rate and average return summarise how often and how strongly the market gained within it.

Methodologically the tool uses normalised returns: each individual meeting is scaled so that the price on the decision day t0 sits at 0 %. Only this makes it possible to fairly overlay and average meetings from different price levels and years — rather than via absolute point differences. The dates come, per central bank, from official sources (federalreserve.gov, ecb.europa.eu, bankofengland.co.uk, boj.or.jp and others) and span different lengths of history depending on the institution — for the Fed they reach back to the year 2000. In addition, for the FOMC you can specifically distinguish between rate hikes and rate cuts to test whether the direction of the decision changes the market reaction. A significance test (t-test against zero) indicates whether an observed effect is statistically robust or more likely chance.

This analysis is a descriptive, statistical tool, not investment advice and not a forecast of future central bank decisions. It shows how a market behaved in the past around meeting dates — whether the central bank raises, cuts or holds the rate is not known in advance and is not part of the analysis. The significance depends on the number of meetings in the selected window: few events produce statistically thin averages. Market moves around central bank dates also have many causes — economic data, geopolitics, liquidity — that cannot be cleanly separated from the meeting effect itself. Use the results as context for your own research, not as your sole basis for decisions. Past patterns do not guarantee future results.

Frequently Asked Questions

What is the pre-FOMC drift? The pre-FOMC drift refers to the tendency — observed in some studies — of US equities to gain slightly in the hours and days before a Fed decision (t0). The event-window tool makes such run-up patterns visible: if the average curve already rises to the left of t0, a run-up effect was present in the selected period. Whether it recurs in the future cannot be inferred from this.

Why is t0 the second meeting day? The Fed (FOMC), the ECB and some other central banks meet over two days. The rate decision is only published on the second day — this announcement day is the decision day and therefore t0. If the date falls on a holiday or weekend, the tool uses the next trading day as the reference point.

Which central banks does the tool cover? The tool lists meeting dates for the Fed (FOMC), ECB, Bank of England, Bank of Japan, SNB, Bank of Canada, RBA and RBNZ. The market-reaction analysis with the event-window chart is currently available for the Fed, ECB, BoE and BoJ — including the Fed-specific filters for rate hikes and rate cuts. Which central bank is relevant for a ticker depends on the trading venue or currency.