From Time to Time
The sixth chapter relates the changes in closure and volatility to general political developments, but it mainly concerns itself with opposing the birth year of party systems to their age. Of course, within the group of currently existing systems these two coincide, but if one adds to the pool historical cases, then one can investigate whether those systems were more closed that were established earlier, or those which had a higher age. We check the importance of these two features not only for closure but also for volatility. While we question the ability of the volatility index to tap systemic features of party politics, we consider it as a relevant indicator of demand-side stability. By relating volatility to closure, the chapter reveals how the demand and supply sides of party politics, the electoral and governmental arenas, connect to each other.