Based on the results of a referendum, Italy will be changing the size of its Chamber of Deputies from 630 to 400. By the cube root law (Taagepera, 1972) a country the size of Italy (around 60.5 million) should have about 392 seats in its first chamber. I’d say 400 is “about 392” and so this outcome is an obviously good thing.
Thanks to Matthew Bergman, Miroslav Nemčok, and Rein Taagepera for calling this to my attention. Rein also sent along an Italian newspaper article (PDF, a bit blurry) in which he was quoted.
The assembly reduction proposal was advanced by the Five Star Movement. As Rein said in personal communication, “sometimes populists get it right.”
Also, the Italian Senate is being reduced, to 200 (from 315, not counting appointed senators). I am not aware of any predictive model for how large a given second chamber “should be”, at least in unitary systems, but I note that in A Different Democracy, 2014, p. 214, we report that the mean second chamber in a unitary state is 0.53 times the size of the first chamber. So Italy is continuing to follow this pattern.