Juggling MMP

One of the common questions that arise when considering changes to MMP is what effects those changes will have. While this is difficult to do for future elections, as voting patterns inevitably change with the system, we can judge from past elections. And now Keri Henare has developed an online calculator to do it automatically, allowing you to set thresholds and whether overhangs are allowed. It automatically calculates both the results and the Gallagher Index, allowing the proportionality of various systems to be compared.

You can play with it here.