It's a function of reductions in child mortality rates.

因为这意味着幼儿死亡率下降了。

Since 2012, they've helped bring down the child mortality rate here by almost 50 percent.

自 2012 年以来，他们让当地的儿童死亡率降低了将近 50%。

Families are going hungry, and reports indicate child mortality rates have increased in the past years.

家家户户食不果腹，还有报道称儿童死亡率在过去几年间骤增。

For most of human history, life expectancy was very low and child mortality rates were very high.

在人类历史的大部分时间里，平均寿命很低，儿童死亡率很高。

And child mortality rates halved worldwide in the same time period.

同期全球儿童死亡率减半。

It took into account child mortality rates, obesity rates, health care, diets, cultural lifestyles.

它考虑了儿童死亡率、肥胖率、医疗保健、饮食、文化生活方式。

But as child mortality rates declined, and the US industrialized, the average family size declined from 7 children in 1800 to 3.5 children by 1900.

但随着儿童死亡率下降和美国工业化，平均家庭规模从 1800 年的 7 个孩子下降到 1900 年的 3.5 个孩子。

To speed up improvement in child mortality rates worldwide, government officials from Ethiopia, India, and the United States, along with UNICEF, held the “Child Survival: A Call To Action” summit in Washington, D.C., last June.

为了降低全世界儿童死亡率，去年6月份，埃塞俄比亚、印度、美国政府和联合国儿童基金会(UNICEF)在华盛顿召开名为“儿童生存: 呼吁采取行动”的峰会。

Thanks to that and other improvements  in medicine, housing, and nutrition, the child mortality rate started to  drop significantly over the century, adding yet another reason why the life  expectancy and population numbers were rising.

由于医疗、住房和营养方面的这一改进以及其他改进，本世纪以来儿童死亡率开始显着下降，这又增加了预期寿命和人口数量上升的另一个原因。