Yes, type "U" refers to Unknown for the Nominal Annual Rate.

是的，“U”型指的是未知的名义增长率。

youdao

Chinese nominal imports (excluding oil) have grown at a compound rate of 12.2 percent since 1995, with much of the demand being met by regional producers.

1995年以来中国的名义进口额(不包括原油)每年递增12.2%，很大一部分需求是由区域内的生产厂商满足的。

youdao

In an emerging economy with rapid productivity growth the real exchange rate should rise over time, through either higher inflation or a rise in the nominal exchange rate.

在一个生产率迅速增长的新兴经济体国内，其实际汇率也会随着时间的推移而上升，方式则可能要么通过高通货膨胀率，要么就是名义汇率的上升。

youdao

So we would say the real interest rate equals the nominal rate-- approximately equals--the nominal rate minus the inflation rate.

我们可以推出实际利率约等于,名义利率减去通货膨胀率

耶鲁公开课 - 金融市场课程节选

The real interest rate, computed from nominal rates, is equal to one plus the nominal rate divided by one plus the inflation rate, so it corrects for inflation.

由名义利率算得的实际利率 等于,/,它是一个经通胀调整后指标

耶鲁公开课 - 金融市场课程节选

Remaining consistent with this principle, Brian argues that when the Fed Funds rate (the rate set by the Fed) is lower than the nominal growth rate, the Fed is inflationary, and when the Fed Funds rate is higher than the nominal rate, the Fed is deflationary.

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There is no problem running a deficit so long as it is lower (as a percent of GDP) than our rate of nominal GDP growth.

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So, if we observe an economy, in which the interest rate was below the nominal growth rate and inflation was not increasing what might we conclude?

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