Fertility of immigrant groups in Denmark by generation

It's somewhat of an alt right myth that immigrant groups come into the country, and then continuously outbreed the original population even if no more immigration happens. While this maybe have happened historically, it does not generally happen in Western countries because the immigrant groups quickly reduce their fertility levels to the level of the host country (demographic transition). Some years ago, I was curious about this fear, so I obtained some Danish data from directly from Danish Statistics (gov stats body). They are shown below, by generation. I left the names in Danish, but they are pretty readable (I added a new pointers in [brackets]). I included only those with at least 10 births in the period to avoid excessive sampling error, and I lined up the countries that match across generations. The correlation between the fertility rates is .57 (n = 15). Original Danish file. These data cover years 2008-2012 (average). First generation     Second generation     Origin Births Fertility rate Origin Births Fertility rate Tyrkiet 681 2,073 Tyrkiet 398 1,679 Polen 501 1,635 Polen 34 1,683 Irak 459 2,248       Somalia 409 3,531       Libanon 347 2,553 Libanon 81 1,542 Pakistan 302 2,732 Pakistan 171 1,772 Tyskland [Germany] 300 1,486 Tyskland 20 1,616 Norge 266 1,713 Norge 15 1,596 Bosnien-Hercegovina 258 1,529       Afghanistan 243 2,506       Thailand 242 1,562       Sverige 239 1,826 Sverige 16 1,445 Vietnam 226 1,989 Vietnam 18 1,050 Island 210 2,112 Island 10 2,201 Filippinerne 201 1,050       Kina 195 1,372       Ukraine 183 1,693       Litauen 164 1,567       Rumænien 153 1,317       Rusland 148 1,737       Iran 143 1,290       Marokko 143 2,861 Marokko 64 1,993 Sri Lanka 135 1,744       Jugoslavien (eks.) 130 1,763 Jugoslavien (eks.) 94 1,783 Storbritannien [Great Britain] 100 1,762 Storbritannien 12 1,898 Indien 90 1,444 Indien 14 1,445 USA 84 1,396       Syrien 82 3,073       Letland 81 1,444       Nederlandene 77 2,027       Brasilien 73 1,559       Makedonien 64 2,050 Makedonien 15 2,166 Frankrig 60 1,450       Bulgarien 53 1,280       Myanmar (tidl. Burma) 53 3,458       Finland 51 1,485       Spanien 43 1,088       Ghana 41 2,191       Jugoslavien. Forb. Rep. 38 2,285       Kuwait 37 2,937       Ungarn 34 1,123       Estland 33 1,605       Uganda 33 1,655       Nigeria 32 2,972       Peru 31 1,972       Canada 30 1,511       Italien 29 941       Jordan 27 3,228 Jordan 23 2,721 Japan 26 1,114       Indonesien 25 1,706       Congo. Demokratiske Republik 22 3,421       Nepal 22 1,221       Etiopien 22 2,117       Hviderusland [Belarus] 22 1,655       Kenya 22 1,449       Kosovo 22 3,353       Mexico 21 1,451       Australien 21 1,564       Serbien og Montenegro 21 1,852       Serbien 20 2,856       Israel 20 2,370       Egypten 20 2,417       Tanzania 19 1,932       Tjekkiet 19 1,279       Burundi 19 2,530       Cameroun 19 2,343       Bangladesh 19 2,617       Tunesien 19 2,815       Congo 18 3,005       Slovakiet 18 1,214       Argentina 17 1,966       Sudan 17 2,805       Chile 16 1,578       Algeriet 16 2,814       Belgien 16 1,592       Sydafrika 15 1,980       Elfenbenskysten [Ivory coast] 15 3,351       Venezuela 15 2,010       Colombia 15 1,176       Østrig [Austria] 14 1,432       Zambia 13 2,198       Irland 13 1,446       Cuba 13 2,070       Statsløs 13 2,492       Gambia 12 1,778       Schweiz 12 1,192       Portugal 12 981       Mellemøsten uoplyst [unknown middle east] 11 3,414       Moldova 11 2,093       Malaysia 11 1,371       Armenien 11 1,632       Sovjetunionen (eks.) 11 1,613       Usbekistan 11 3,108       Kroatien 10 1,744       Sierra Leone 10 2,911      

If one avoids breaking down by country, one can also get some neat longitudinal data that gives useful perspective with updated data (FERT1 table).

So, current 'Danish origin' (some partial foreigners in this group) fertility sits at ~1.8, which is good by comparison with developed countries in general. It can be seen that non-western 1st generations had a large decline since the 1980s and now roughly matches the other groups, though with a slight increase since 2012 or so. Immigrant women from western countries do not have many offspring. These probably represent a lot of power women who come to Denmark to work, and then neglect family life. 2nd generation non-westerns do not have particularly high fertility. This is surprising considering the relative low IQ of this group (85-90), and the known relationship between lower IQ and fertility (r = -.11 according to recent meta-analysis). In this case, the group level factors seem to overwhelm the expectation based on the individual level differences.