Gekko 1.6

Gekko is a free time-series oriented software package for solving and analyzing large-scale economic models. Since 2009, Gekko is being used by Danish ministeries, banks, interest groups and universities, for the simulation of economic and energy-related models (more). The software runs under Windows (.NET), and is open source (GNU GPL).

Some features:

Timeseries-oriented software.
Flexible data banks: annual, quarters and months.
Dynamically loaded and compiled models.
Gauss and Newton solvers, with ordering and feedback logic. Fair-Taylor solver for forward-looking models.
Any number of simultaneous goals/means possible.
Failsafe mode for simulation.
In-built equation browser, with variable list.
Decomposition of changes in equations.
Double precision, missing values handled consistently
Expressions accepted anywhere: in print, plot, etc.
Strict language syntax (via in-built ANTLR parser), with loops, conditionals etc. (more of this to come).
Graphics by means of embedded gnuplot
Tabelling and menu system, outputting in text, html or Excel
Read/write from Excel or other spreadsheets.
Used by Statistics Denmark, Ministry of Finance, Ministry for Economic Affairs, Danish Energy Agency, Technical University of Denmark, universities and more.
Easy installation by means of a all-inclusive Windows installer, or manually by means of a zip-file with gekko.exe etc.
Open source. No licenses to compilers etc. -- everything used is C#/.NET (+ gnuplot and 7zip). So everything is open-source, and therefore free of charge.