

    \filetitle{!exogenous\_variables}{List of exogenous variables}{modellang/exogenousvariables}

	\paragraph{Syntax}

\begin{verbatim}
!exogenous_variables
    Variable_Name, Variable_Name, ...
    ...
\end{verbatim}

\paragraph{Syntax with descriptors}

\begin{verbatim}
!exogenous_variables
    Variable_Name, Variable_Name, ...
    'Description of the variable...' Variable_Name
\end{verbatim}

\paragraph{Syntax with steady-state
values}

\begin{verbatim}
!exogenous_variables
    Variable_Name, Variable_Name, ...
    Variable_Name = Value
\end{verbatim}

\paragraph{Description}

The \texttt{!exogenous\_variables} keyword starts a new declaration
block for exogenous variables, i.e.~variables that can appear only in
\href{modellang/dtrends}{\texttt{!dtrends}} equations. The names of the
variables must be separated by commas, semi-colons, or line breaks. You
can have as many declaration blocks as you wish in any order in your
model file: They all get combined together when you read the model file
in. Each variable must be declared (exactly once).

You can add descriptors to the variables (enclosed in single or double
quotes, preceding the name of the variable); these will be stored in,
and accessible from, the model object. You can also assign steady-state
values to the variables straight in the model file (following an equal
sign after the name of the variable); this is, though, rather rare and
unnecessary practice because you can assign and change steady-state
values more conveniently in the model object.

\paragraph{Example}

\begin{verbatim}
!exogenous_variables
    X, 'Tax effects' Y
    'Population growth effects' Z = 0 + 0.5i;
\end{verbatim}


