UNICEF, the World Health Organization, the World Bank, and the United Nations released global child mortality data Tuesday, and the results are very encouraging. Out of 195 countries, only six — Barbados, Botswana, Lesotho, Niue, Swaziland and Zimbabwe — saw mortality rates for children under five increase between 1990 and 2012.

Every other country saw declines, often big ones. Child mortality declined by about 74 percent in China, 77 percent in Brazil, 81 percent in Bangladesh, nearly 56 percent in India, and more than 61 percent in Russia. The biggest gains were in developed countries, but developing ones, even in sub-Saharan Africa, saw lots of progress too:

Credit: UNICEF, the World Health Organization, the World Bank, and the United Nations

This is not to say, of course, that the task of reducing mortality for newborns and those under 5 is anywhere near complete. The fourth of the United Nations' eight Millennium Development Goals was to reduce under-five mortality by two-thirds between 1990 and 2015. Between 1990 and 2012, it only fell by 47 percent, and we would have to make much, much faster progress if the two-thirds goal is to be reached in two years.

And the raw numbers are still sobering: 6.6 million children died last year before their fifth birthday. The vast majority of those deaths were totally preventable. If you're interested in reducing that number, by the way, among the most effective ways is to increase access to netting that can be used to protect people from mosquitoes, which the Against Malaria Foundation does extremely well.

So we have a lot further to go. But this is an important reminder that global development is proceeding much faster than many realize.