This calculator is part of my C++ class library of chess rating systems. Please go to introduction page for further information.
IECG is a now withdrawn e-mail chess club. Its rating rules are employed by its successor Lechenicher Schachserver (LSS). The rocket player formulas are implemented, but unfortunately I lack test data for them. As LSS calculates daily batches the established rating rocket player rule should be of little practical use now.
If you have less than 15 games, you must include all your games, not only the ones from the last period. Old rating is your initial rating.