This Gapminder chart graphs the number of children per woman against the percentage of the population with access to clean water.

Have you ever wondered if the quality of a child's teeth is related to the GDP per capita of his or her country?

Thanks to a Swedish website called Gapminder, you now have the chance to find out — and to discover stranger correlations yet. The site gives users the chance to create graphs of everything from fertility to the number of broadband Internet subscribers in a given country. That way, they can explore the ways that these indicators may or may not be connected. The resulting charts make dealing with statistics not only easier than usual, but also a little bit addictive and fun.

Aside from the fun factor, the site is meant to be a serious tool: It aims to support the UN Millennium Development Goals by making relevant statistics more accessible, with data sets drawn from international organizations and corporations ranging from UNESCO to the British oil company BP.

I'm interested in women's issues, for example, and Gapminder makes it enjoyable for me to get an idea of how the average age of a woman when she first marries correlates with the life expectancy in her country. Watching the dots fly across to the screen in a good approximation of a slanted line tells me that the two factors do, in fact, correlate very well. Of course, the golden rule of statistics — that correlation doesn't equal causation — still applies, so I don't know if one of these factors actually caused the other. Did women get married later because they were living longer, or did getting married later contribute to population longevity when fewer women died young in childbirth, for example? Or — as seems more likely — does a population live longer and get married later because it's getting wealthier or more educated? My graph is sworn to silence on such questions, but Gapminder does make it easy for me to investigate further with a new chart and a different measurement, like GDP or education levels.

There are more caveats, too. Data isn't available for all years on all topics in all countries, partly because the data sets come from such disparate organizations and partly because these organizations weren't always around to do the counting. If you want to know how GDP per capita correlated with infant mortality in the early 1800s, you'll only have two countries to compare — Sweden and Austria. And any data set is only as good as the government or organization that collects it: a notice on the website points out that their population numbers for the U.S. before 1900 include neither African Americans nor Native Americans.

By providing open access to a tool that makes analyzing statistics easier, Gapminder is helping make such data more democratic, more transparent, and, perhaps, a little more honest.