That number has been declining steadily since the 1950s.

这个数量自从1950年就开始下降。

Then production and availability will begin to seriously decline.

然后产量和可获得的数量将会开始急剧减少。

Revenues are declining at all three networks.

三个公司的总收入都下降。

Over recent years they haven't yet declined.

近年来也没有下降。

And though print ad sales still dwarf their online and mobile counterparts, revenue from print is still declining.

尽管纸质版纸的广告销售额仍和移动纸相形见绌，但是纸质版纸的收入仍下滑。

The flying insects that swifts eat also appear to be declining.

食的飞虫似乎也减少。

Global production has been declining since 2004 while consumption has risen.

全球产量自2004年开始下降，而消费量却上升。

So the species they're eating the most of are not declining.

所以，它们食的物种并没有减少。

Cattle are already being affected because the quality of their forage is declining.

由于草饲料质量的下降，牛也已经受到了影响。

People would see that, oh, the health of the grass is declining.

人们会看到，哦，草原的环境每况愈下。

And they're showing that the antibody levels are declining over time.

他们表明抗体水平随着时间的推移而下降。

The Dow Jones Industrial Average endured its eighth biggest point decline ever on Monday.

周一，道琼斯工业平均指数创下第八大单日最大跌幅。

But her health, it was declining.

但她的健康状况每况愈下。

But there are two clues that tell you that she is declining my invitation.

但是，有两点暗示了她婉拒我的邀请。

Why then is their importance declining?

那他们的重要性怎么还会下降呢？

Repeat testing helps scientists track any decline.

重复检测帮助科学家追踪任何指标的衰退情况。

Which those groups had the biggest declines?

哪些群体的减少得最多呢？

Karl Marx wrote in the 1830s and 1840s about how workers' wages were declining.

卡尔·马克思十九世纪三四十年代写过工人们的薪水如何缩水。

And that's what we're actually seeing in places like California where kelp forests are declining.

这就是我们加州等地所看到的，那里的海藻林正减少。

He was 81 and in declining health.

他当时已经81岁，健康状况每况日下。