Child mortality is decreasing, but 6.3 million children under the age of five still died last year.

Of those deaths, 44% came in the womb, or the first 27 days of a baby’s life, according to a study published in The Lancet and conducted by Johns Hopkins.

In children one month to 5 years old, pneumonia and diarrhea were the most common causes of death.

Overall, child mortality has decreased since 2000, when 9.9 million children died. The decrease is largely due to the reducing incidence of pneumonia and diarrhea in southern Asia, and a similar trend in malaria, measles and diarrhea in sub-Saharan Africa. Efforts to reduce some of these causes dovetail into each other—children with HIV are especially susceptible to both pneumonia and diarrheal disease, for example, so a lower rate of HIV helps reduce pneumonia. Clean drinking water and improved hygiene reduce the spread of diarrheal disease.

Still, sub-Saharan Africa accounted for 49.6% of the deaths in 2013, and Southern Asia 32.1%. The five countries that see the most deaths are India, Nigeria, Pakistan, the Democratic Republic of Congo, and China.