As they say in Italian, Così va il mondo. For our US readers, hardly any of whom speak the language anymore, let me translate: “So the world goes.”

From 2001 to 2017, the number of Americans speaking Italian at home dropped from almost 900,000 to just over 550,000, an incredible 38% reduction in just 16 years. Among languages with at least 100,000 US speakers in 2001, no language saw a larger decrease, in either absolute or percentage terms—though Hungarian was close by percentage. The data is from the US Census.

Fastest declining languages spoken at home in the US

Language 2001 2017 Change Italian 893,000 554,000 -38% Hungarian 104,000 64,000 -38% German 1,203,000 905,000 -25% Greek 341,000 269,000 -21% Polish 604,000 512,000 -15% French 1,349,000 1,185,000 -12%

The rapid decline of Italian in the US is due to two major factors.

The first one is very simple. There are many fewer Italian-born residents of the US today. The population fell from about 530,000 in 2001 to under 400,000 in 2017. This explains about 40% of the fall in Italian speakers. The lack of migration to the US is largely due to the increasing prosperity of Italy across second half of the 20th century—while US GDP per person was almost double that of Italy in 1960, it is only about 50% greater today.

Also, free movement within the EU made migrating to the UK, another rich English-speaking country, more appealing than going to the US. The number of Italians grew by almost 70,000 in the UK from 2000 to 2017.

The other 60% of the fall is mostly accounted for by assimilation. From 1930 to 1970, there were more foreign-born residents of the US from Italy than any other country. As these immigrants die and their descendants start families in which they speak primarily English, the number of Italian speakers dwindles further. The number of German speakers in the US is falling for similar reasons.

Though Italian is in decline, due to an increase in immigrants from Asia and Latin America, the number of Americans that speak a language besides English at home is rising. Just 11% of US citizens spoke another language at home in 1980, compared to 22% in 2016. As my colleague Ananya Bhattacharya points out, the increase in the number of speakers of South Asian languages, like Telugu, is more than making up for the loss of Italian.