These guidelines apply to any time series published by the U.S. Census Bureau that is seasonally adjusted or is part of a seasonally adjusted composite series. A seasonal adjustment of a time series removes seasonality and/or other calendar effects, such as trading day and moving holiday effects. Trading day effects are recurring effects associated with the weekday composition of the month. Moving holidays are holidays that are not always on the same date, such as Easter. A composite series is a series that is a combination, usually a sum, of other time series.