User guide

Using Excel with Datastream Advance for Office
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USING FUNCTIONS AND EXPRESSIONS WITH TIME SERIES REQUESTS
Selecting expressions
For time series data requests, you can browse and select expressions stored on the Datastream host system.
The Time Series Data Request Expression Picker, displayed by clicking the Expression button , on
the Time Series Request screen, can display all user created expressions or Datastream global expressions, or
both. See Using Expressions. A Refresh Grid button enables you to update the list of expressions held on your
PC from the Datastream host system.
Expressions can be used for time series requests where only one symbolic variable is used. For example,
PCH#(X,1Y) calculates the percentage change over one year where X is either a single series or a constituent of
a list that you select.
Example - Percentage change over one year of market index constituents