IF A baby is born in a rich country, she will have a longer, healthier life with more economic opportunities than one born in a poor, conflict-ridden nation. But quantifying the value of a person’s nationality compared with another is tricky. The number of countries that a person can travel to or settle in without bureaucratic restrictions may be one indicator, but the appeal of those countries is just as important. Russian nationals can travel to over 100 countries without a visa, for instance, but none are rich economies. Similarly the size of an economy may be a large factor, but it does not account for settlement opportunities elsewhere. Americans benefit from living in the world’s largest economy yet they can settle in only a handful of smaller economies. An inaugural “quality of nationality index” (QNI) by Henley & Partners, a consultancy, attempts to do just that by looking at the value of citizenship on two counts: to a person living in the country (the internal value) and the ability to live or work elsewhere (the external value). The internal value combines a nation’s economic heft, its score on the UN’s human development index, and its peacefulness and stability. The external value measures the number of countries that a citizen may travel to and settle in, and the weight of those in terms of economic strength and stability.

In 2015 all of the top 32 spots were European, boosted by economic integration and the right to free movement and work. Germany’s position at the top reflects its stability, economic strength and the ability of its citizens to travel and work in strong and stable economies elsewhere. The United States ranks behind European Union states for two reasons: a lower score on peacefulness (measured on the Global Peace Index), due to its nuclear arsenal and involvement in armed conflicts, and a low score on settlement freedom. And as Britons prepare to vote on whether to leave the European Union on June 23rd, another filip to the Remain campaigners. Dimitry Kochenov, creator of the index, calculates that Britain would fall from 11th to 30th in the ranking were it to leave, placing it behind Japan.