Market Catalysts

How Release Dates Get Moved

Updated

Schedules are plans, not guarantees

Most of the events on this site are scheduled months in advance. Statistical agencies publish release calendars for the year ahead, the Federal Reserve sets its meeting dates more than a year out, and market-structure events follow fixed rules. That predictability is what makes a catalyst calendar useful.

But dates do move. Usually the change is small and announced well ahead; occasionally it is sudden and large. This guide covers the main reasons dates shift and explains how this site labels the certainty of each date.

How this site labels dates

Every event on this site carries one of three labels.

Label What it means Typical examples
Confirmed Read directly from the publisher’s own published schedule. CPI, the jobs report, GDP, FOMC meetings, NYSE holidays
Computed Derived from a fixed rule rather than read from a list. Monthly options expiration (third Friday), quad witching, the S&P quarterly rebalance effective date
Tentative The publisher has listed the date but marked it as subject to change. Future FOMC meetings the Fed lists as tentative, some later-year release dates

A computed date is reliable as long as the rule holds, but it can still change if the rule itself has an exception, for example when the exchange is closed on the day the rule points to. A confirmed date can still move if the publisher reschedules. A tentative date is the least certain, and the publisher’s later confirmation replaces it.

Each event also links to the page its date was taken from, so the publisher’s current schedule can always be checked.

Reason 1: holidays

Holidays are the most common and most predictable reason for a shift.

Federal holidays and government data

Federal agencies do not publish on federal holidays. When a report’s normal day falls on one, the agency schedules it for another day. The most familiar example is weekly jobless claims, normally released on Thursdays, which can move in a holiday week. Because agencies set these changes when they publish their annual calendars, the shifted dates are usually known well in advance.

Market holidays and rule-based events

Rule-based events depend on whether the exchange is open. When the stock market is closed on the third Friday of a month, which happens most often on Good Friday, options expiration moves to the preceding business day. The ISM reports, which follow a business-day rule, skip days when the New York Stock Exchange is closed.

When the two calendars disagree

Federal holidays and stock market holidays are not the same. Good Friday closes the stock market but is not a federal holiday, so government data can come out that morning with stocks shut. Columbus Day and Veterans Day are federal holidays when stocks trade normally, so there is no federal data that day even though the market is open. The market holiday explainer lists the NYSE holidays and early-close rules.

Reason 2: government shutdowns

The biggest disruptions come from lapses in appropriations, commonly called government shutdowns. When Congress does not pass funding, many federal agencies, including the Bureau of Labor Statistics, the Bureau of Economic Analysis and the Census Bureau, must suspend most of their work. Data collection stops, and scheduled releases do not go out.

The effects can last well beyond the shutdown itself:

  • Releases are postponed. Once funding resumes, agencies publish revised schedules, often compressing several delayed reports into a short period.
  • Some data are never collected. Survey data that depend on collecting information during a specific window cannot always be gathered after the fact.
  • Gaps carry forward. A missing month can affect later calculations, such as year-over-year comparisons a year later.

The lapse in appropriations from October 1 to November 12, 2025 is a documented example. BLS rescheduled many releases and did not publish an October 2025 CPI news release, because most of that month’s price data could not be collected. BLS has described the effects, including on later 12-month comparisons, in its FAQ on the shutdown’s impact on the CPI.

Not every publisher is affected. The Federal Reserve is not funded through congressional appropriations, so FOMC meetings, minutes and the Beige Book continue during a shutdown. Private publishers such as the Institute for Supply Management and the University of Michigan carry on as usual, as do exchanges and index providers. Treasury auctions also continue. During a shutdown, these become the main sources of fresh information.

When a shutdown looks possible, this site cannot know in advance which dates will be lost. Dates stay as published until the publisher announces a change.

Reason 3: publisher rescheduling

Publishers sometimes move dates for their own reasons:

  • Operational issues. Technical problems, data processing errors or system changes can delay a release.
  • Methodology changes. A major update to how a series is calculated can lead an agency to adjust its timing for a period.
  • Calendar adjustments. Agencies occasionally shift a date to avoid clashing with other releases or to accommodate changes in source data.
  • Federal Reserve meetings. The FOMC sets its schedule well ahead, lists later dates as tentative until confirmed, and can hold unscheduled meetings when conditions require. An unscheduled meeting, by its nature, cannot appear on a calendar in advance.

Index providers change schedules too, usually with long notice. FTSE Russell’s move from annual to semi-annual Russell reconstitution is an example of a schedule rule changing outright, which affects every future date derived from it.

Reason 4: rules with exceptions

Some events follow rules that have built-in exceptions:

  • The jobs report usually comes out on the first Friday of the month, but the date depends on when the survey reference week falls, so it is sometimes the second Friday.
  • The ISM Manufacturing PMI comes out on the first business day of the month, except in January, when it moves to the second.
  • The ISM Services PMI comes out on the third business day, except in January, when it moves to the fourth.

These are not schedule changes so much as features of the rule, but they explain why a date may not be where a simple rule of thumb suggests.

Unscheduled closures

Rarely, exchanges close outside their published holiday schedule, for example for a national day of mourning or because of an emergency. Those closures are announced at the time. They can push back rule-based events and leave scheduled data releases landing on a day when stocks are not trading.

Practical habits

  • Check the label. A confirmed date is more reliable than a tentative one.
  • Check the source. Each event links to the page its date came from; the publisher’s page is always the authority.
  • Watch the week ahead. Most changes are announced days or weeks before the event.
  • Expect knock-on effects. When one release moves, others nearby may move with it, especially after a shutdown.

For how to read the rest of the calendar, see how to read an economic calendar.