The Internet is littered with vocabulary tests that appeal to the small portion of the population interested in such things.
To date, one of these tests has been taken by at least two million people and has accumulated some interesting data. I discovered the site by way of an article in the Economist. According to the article, it’s “a serious research project.”
The test consists of several hundred words with check boxes beside each one. The test-taker checks the box next to known words and leaves the other blank. Questions at the end gather the following information:
Native or non-native English speaker
Date of birth
Reading habits (“Lots,” “Somewhat,” “Not Much”)
Fiction reading habits (“Lots,” “Somewhat,” “Not Much”)
Test-takers are also asked to give their SAT scores if they know them. According to the self-reporting response to this question, participation is “in roughly the 98th percentile of the American population as a whole.”
Most native English speakers who take the test have vocabularies ranging from 20,000-35,000 words. ESL speakers tend to have about 4,500. According to the site’s interpretation of results, acquisition of new vocabulary falls off in middle age. Adult vocabulary size appears to be principally determined by reading habits between ages 4 and 15.
As might be expected, the more you read, the more your vocabulary increases.
Children between the ages of four and fifteen who read “lots” learn +4.1 words a day. For those who read “somewhat,” the rate is +2.6 words a day, and for the “not much” cohort, +1.4 words a day. Reading fiction is as important for vocabulary growth as reading in general.
To take the test, go here: http://testyourvocab.com/
By the way, it’s considered bad form to reveal your score or to ask others how they scored.