Water is an issue of global importance. But how has access to clean water changed over time?

National Geographic tried to answer that question this week with “See Where Access to Clean Water Is Getting Better—and Worse.” The article uses dynamic graphics to help audiences visualize the numbers.

One chart tracks the proportion of the population without access to improved water, with data from the past 25 years. Readers can toggle the chart to see data by individual country, by world region, and for the world as a whole. For each selection, readers can see results for the entire population, or separately for that region’s urban and rural populations.

The article points out that while rural access has improved more than urban access has, urban access is still on average greater. There are also significant differences in access according to region.

Access to water is understandably a major political and social issue.

The United Nations recognizes water as a basic human need, and has held several conferences and summits to help address this issue over the past several decades.

In July 2010, the United Nations General Assembly recognized the human right to water and sanitation.

January 1, 2016 marked the end of the International Decade for Action “Water for Life” 2005-2015.

What do you think is the most pressing world water issue? How should politicians, companies, non-profits, and people around the world try to address these issues?