LAST YEAR we looked at the first-ever global survey of English-language skills by EF Education First, a teaching company. This year, EF has produced its second study of the same subject. It's worth revisiting for the changes between last year and this one. First, I'll repeat my caveat from last year: "This was not a statistically controlled study: the subjects took a free test online and of their own accord. They were by definition connected to the internet and interested in testing their English; they will also be younger and more urban than the population at large. But Philip Hult, the boss of EF, says that his sample shows results similar to a more scientifically controlled but smaller study by the British Council." The test will obviously not reach poor and rural folk who lack internet access. So if a country has an urban elite who are good with English, and a lot of rural poor people who cannot take the test, its score might be relatively inflated. In another country where nearly everyone is online but English skills are mediocre, the scores might be relatively depressed. Despite that, the index has value. It is based on the test results of a huge sample: 1.7m people over three years in more than 50 countries. For the first time this year, gender, age, industry and job-level are broken out for those who want to get further into the data. (Spoiler alert: women do better than men, and the 30-35 set does best in terms of age. Those working in tourism do better than those working in mining and energy.) Fascinating individual country reports, including regional maps, are here. We learn, for example, that Moscow compares with Austria in its English skill, while Russia's Urals region compares with Qatar or Mexico.

Last year, the biggest surprise to me was that China and India were ranked alongside each other, despite India's much better reputation for English skill. That has changed this year, owing to a methodological tweak. India is now well ahead. Michael Lu of EF explains in an e-mail:

The 1st EF EPI report was based on four tests and in the 2nd report, we removed one of the four tests that didn’t fully test listening skills (it was optional). This change was made to ensure the EPI gets more accurate over time. Countries that are better at vocabulary/grammar/reading and weaker at listening had their rankings slightly inflated in the 1st report, as was the case with China. Conversely, countries such as India which are better at listening moved up in rankings.

In addition, he notes that 12 countries were added to the survey, and that the scores are very close to each other. For that reason, countries may seem to have moved quickly up or down the rankings despite no great real-world change in their English skills in the year. Many of the newly added countries ranked ahead of Brazil, for example, and that plus a slight score change caused Brazil to fall 15 places in the rankings. The index, Mr Lu says, should get more accurate over time as data continue to come in and the methodology is refined.

Clarification: This post originally referred to the company that undertook the study as "EF Englishtown". EF Englishtown is one divison of EF Education First, the parent company responsible for the survey.