Part of the complex process of misguiding voters about the economy...

I need one piece of data. I googled quarterly Real GDP data for 1946. I just need the data for the last quarter of 1946, if it exists, so I can get the growth rate for 1947 Q1. But then I would have to "annualize" that quarterly rate, to make it compatible with the FRED data.

In the same search, Google's "People also ask" turned this up:

How do you annualize quarterly data?

To annualize a number, multiply the shorter-term rate of return by the number of periods that make up one year. One month's return would be multiplied by 12 months while one quarter's return by four quarters.

Annualize: Definition, Formulas, and Examples - Investopedia

I know there are 12 months in a year. I know there are four quarters in a year. For me, the P.A.A. question is interesting because I want to know how economists handle compounding. Do they ignore it? I doubt it. But the P.A.A. answer from Investopedia seems to ignore compounding. Or maybe Google just left it out. We will see.

I read the Investopedia article even though they are low on my 'trustworthy' list. This is what I found:

To annualize a number means to convert a short-term calculation or rate into an annual rate. Typically, an investment that yields a short-term rate of return is annualized to determine an annual rate of return, which may also include compounding or reinvestment of interest and dividends. It helps to annualize a rate of return to better compare the performance of one security versus another. 

Yes, convert to an annual rate.

Yes, "may" include compounding. That's why we're here.

Yes, annualizing is helpful when comparing data, because growth is "typically" annualized. Sometimes it is hard to find monthly or quarterly data that is *not* annualized, and you have nothing to compare your data to unless you annualize it.

But Investopedia reduces their answer to "key takeaways":

• To annualize a number, multiply the shorter-term rate of return by the number of periods that make up one year.
• One month's return would be multiplied by 12 months while one quarter's return by four quarters.

There is nothing in the key takeaways about compounding. But just after the key takeaways, they say this:

If the yield being considered is subject to compounding, annualization will also account for the effects of compounding.

What? What are they trying to say? They tell me to take one quarter's growth and multiply it by 4 to get the year's growth.. Then they say that this "will also account for compounding" if my data "is subject to compounding". That's bullshit. I think what they mean to say is, if my data is subject to compounding, the compounding must also be figured. But they say nothing of the kind. 

This is why I don't trust Investopedia.

I searched their article for the word "compound". It occurs four times, all four with the "ing" ending:

• "Typically, an investment that yields a short-term rate of return is annualized to determine an annual rate of return, which may also include compounding or reinvestment of interest and dividends."
• "If the yield being considered is subject to compounding, annualization will also account for the effects of compounding."
• "Let's say a stock returned 1% in one month in capital gains on a simple (not compounding) basis. The annualized rate of return would be equal to 12% because there are 12 months in one year."

In the second of those three sentences, I think they mean annualization should also account for the effects of compounding. But that is not what they say. Their words indicate that the compounding is taken care of automatically when you multiply by 12 or by 4.

As I said: Bullshit.