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seasonal adjustment

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Air Traffic Methodology

Explanation of estimates

Estimates derived from a forecast of the data. The first estimate is a two-month ahead forecast of the data. When an additional month of data become available, BTS uses the data to re-forecast the month and releases a second estimate. BTS performs the forecasting...

Seasonally Adjusting Vehicle Miles Traveled

For the most recent data and model used for seasonal adjustment, visit: https://data.bts.gov/Research-and-Statistics/Transportation-Services-Index-and-Seasonally-Adjus/bw6n-ddqk

Seasonal Adjustment

Vehicle-miles traveled (VMT) are key data for highway planning and management,...

Seasonally-Adjusted Data: What it Really Means

This paper provides a brief overview of what it means when data are seasonally-adjusted and describes the advantages of using seasonally adjusted data to examine changes in data. The Bureau of Transportation Statistics’ airline data are used as an illustrative example. For the most recent data...

Seasonally-Adjusted Transportation Data

Seasonal adjustment is the process of estimating and removing movement in a time series caused by regular seasonal variation in activity, e.g., an increase in air travel during summer months. Seasonal movement makes it difficult to see underlying changes in the data. Monthly shifts in data as...