Detrend

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Every contract or stock that is selected for charting or inclusion in a portfolio can be automatically detrended.

Why Detrend?

Detrending is a manipulation that attempts to remove long-position biases and other distortions that can occur in long-term analysis. It is a useful procedure for all types of continuous files.

Please note that due to the effects of inflation and deflation, back-adjusted and forward-adjusted files can produce negative values. The same adjusted price series may, in fact, go negative in both back- and forward-adjusted files, depending on the rate of ascent or descent. The tendency to go negative may be reduced or eliminated when data is detrended. However, detrending will not guarantee that adjusted data will be elevated out of negative territory. Detrending is only one way that a user might minimize the likelihood that the back-adjusted historical past will fall into negative territory.

UA detrends linearly from the first day of a time series through the second to last day on file or through the last day of the second to last contract.

The detrending approach always focuses upon the very first (most distant) day of the historical series and either the day before the last day or the last day of the second most current contract. Either of these two selected end points and the first point determine a precise interval on the y price axis. The number of trading days that transpired from the first (most distant) point and the chosen end point determines the number of units (days) by which the entire series will be elevated or decreased, as the case might be, and leads to the slope calculation.

Detrending may be appropriate to condition a data series for analytical use within UA or with third-party software. The transformation of all historical data into today's terms is a convenient analytical tool. Detrending options are:

·	Not Detrended - Leave the box unchecked for no detrending.

·	Detrended - Click the box to check the Detrend setting, Then click the arrow at the right of the adjacent selection box to choose one of the following:

·

Second Contract - Select to detrend the portion of the series that lies earlier than the final (most current) contract segment of the adjusted series.

·

Second Day - Select to detrend right up to the day before the current day of the final contract.

When used for cash series, detrending always affects all data except the balance of the final calendar quarter.

Click the Detrend Method box and make your choice to effectively present all history in current-dollar terms.

Click here to learn about Post-Processing Inversion.