Google says the interactive map, which was a joint initiative between Google Ideas and the Brazil-based Igarape Institute, was pulled together using more than a million data points of small arms, light weapons, and ammunition purchases between 1992 and 2010, based on numbers gathered by the Peace Research Institute Oslo.

"The majority of people around the world are being killed not by bombs but by guns and bullets," explained Robert Muggah, the research director at Igarape, during Google Ideas recent conference in California. (See video below.)

The map (which is best viewed on Google's own browser Chrome) is, at first glance, a blur of bright streaks that cross a dark globe. However, select a country and play with the filters at the bottom, and information patterns begin to emerge.

InSight Crime Analysis

Perhaps the most startling of these patterns is the incredible amount of money spent on ammunition. Igarape thinks it amounts to half of the estimated $8.5 billion market.

In Latin America, the graphic shows that the biggest importers of ammunition are, not surprisingly, Peru and Colombia, two countries at war. But whereas Colombia's imports were relatively steady in the last three years, Peru out-imported Colombia by close to $10 million in 2010, perhaps a reflection of that government's increasing concerns about the Shining Path guerrilla group.

Perhaps more surprising is that tiny Dominican Republic imported close to the same amount of ammunition as Argentina in the last three years. Or that Mexico imported less ammunition than it exported in 2010.

The United States is, of course, the largest supplier of ammunition. Click on it and see thick red lights dripping heavily into the region's most violence-ravaged countries: Mexico, Colombia, Venezuela, and Brazil, among them.

The market for ammunition, Muggah says, is under-appreciated in gun trafficking research and policy circles.

"Ammunition isn't something governments want to talk about," he said at the Google Ideas conference.

To be sure, as Muggah pointed out in the conference, the United Nations' meeting on controlling small arms and light weapons, held in New York in late August after the Google conference, did not mention ammunition in its 2012 declaration. (See a pdf version of the declaration here.)

The graphic shows that the arms trade remains concentrated in the hands of the wealthy. The top importers and exporters are first world nations such as the United States (who, almost like Olympic swimming, does not have a rival in this field). Russia is second, but the interactive graphic seems to connect to tiny Israel more than it should.

Still, other, smaller countries, like Mexico, have booming arms industries. The graphic shows that in 2010, imports of arms and ammunitions went up by over 400 percent relative to Mexico's historical average, while exports increased by over 200 percent.

According to Igarape, there are 875 million light weapon and small arms in the world. Most of these weapons are, surprisingly, in civilian hands. Igarape estimates that 74 percent are held by civilians; 23 percent are in military hands; while less than one percent are in the hands of suspected terrorists, guerrillas and other armed actors.

These smaller movements are obviously lost in such a giant and ambitious display, as are other layers of data. It would have been revealing, for instance, to layer gun-related homicide data on top of these guns and ammunition movements to see the patterns connecting those two elements.

There also seems to be, for instance, no correlation between war, weapons imports and gun-related violence but it would have been worthwhile to impose another layer illustrating this. As Muggah pointed out in his presentation, countries like Brazil, Mexico, and South Africa have more violent deaths at the hands of guns than the war-ravaged countries Syria, Afghanistan, and Sudan combined.

The Small Arms Survey weighs in:

Dear Steven:

Staff at the Small Arms Survey have brought to my attention your recent report in the Insight Crime monitor - a great initiative I might add - concerning Google's interactive map on the small arms transfers. I would like to offer some additional information that might be important to you.

First, the Google interactive map is just that - a visual presentation of a large number of individual data points. It does NOT provide the foundation for the analysis and figures cited in your report. Second, these figures (including the 8.5 billion USD total trade, or the proportion of the trade that is ammunition) come directly from the Small Arms Survey 2012 yearbook, launched this week in New York. Other figures (including the total number of small arms in circulation and their distribution, inter alia) come from previous work of the Small Arms Survey, of which Rob Muggah was the former research director. It is not Igarape research.

We would be grateful if you could attribute the analysis to the Small Arms Survey. You may also be interested in further details from the Small Arms Survey 2012; see: http://www.smallarmssurvey.org/about-us/highlights/highlight-small-arms-survey-2012-moving-targets.html

Yours sincerely,

Keith Krause

Programme Director, Small Arms Survey

[Editor's Note: InSight Crime added a letter from Small Arms Survey on August 31.]