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This is the way data journalism should be done, kudos!

> exchange rates are from Thomson Reuters

Sorry to say I'm cynical enough to be surprised that they're allowed to republish this data.

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Daily currency and stock data is practically free in most cases. Anyway, this is historical data and not real time. I don't think Reuters gives a fuck beyond your payment for downloading the data in the first place.

Now if you piped the real time API to somewhere else for a broadcast / simple multicast, Reuters may take issue with it.

Yeah almost every brokerage provides access to historical exchange rates
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In finance, the data is all public, and the algorithms are all secret. In oil, the data is all secret, and the algorithms are all public.
I smiled at this. But, as I'm sure you know, historic data is public in finance. There is good business in keeping current data private to sell it.
I suspect the Big Mac index is not super informative in a lot of wealthier areas where the cost of shelter is growing much faster than the cost of food.
I think I'm general inflation indexes are now completely impossible to generalize because (a) inflation has been enormous in some locales and some sectors but (b) the relative price of goods is now so dependent on location.

That is, like you say, in a major city I'd expect a Big Mac to be only slightly more expensive, but I'd expect housing to be astronomical. But outside of probably like 10-15 major metros I'd expect housing to be flat if not negative in huge swaths of the US.

To be at all useful, an inflation index almost has to ignore, say, the rental cost of a 1 BR apartment in the downtown or other sought after area of a relative handful of major cities. After all, in many cases, the same dynamics often don't apply even a 60-90 minute drive away.

On the other hand, the fact that Big Macs and gallons of milk (or houses in Flint Michigan) haven't gone up much in price is more or less irrelevant to the young couple renting in Manhattan and looking for child care.

Those few major cities make up a sizeable portion of the population though, you can't just remove them from the data and call it a day. Perhaps the solution is splitting it into a "high density inflation index" and "low density inflation index".
Consumer pricing is the last to get hit with inflation.

Why do people use CPI instead of labor, housing, or stock prices to gauge inflation?

On a similar note, why would anyone trust the federal reserve's numbers given how the federal reserve has lied in the past?

It is easy to calculate. A gallon of milk today is essentially the same as a gallon of milk 100 years ago. Same with gasoline and cans of beans.
That's not accurate. CPI adjusts both in basket composition and the more nebulous hedonic quality adjustment. The TV you bought for $500 today is not the same as the one you bought for an equivalent price 30 years ago.
People actually in the field don't trust the CPI number as gospel. We all know its shortcomings. However, the CPI print does move the market, so while it is good to keep track of the real inflation number by our own methodologies (which generally involves a different weighing scheme since the real CPI already accounts for most consumer products), you hardly trade on it.

For example, people have been shouting that inflation has already screamed past the Federal Reserve's target (of 2%) if the weight to medicare costs was increased to reflect the true spending of an average consumer(i.e. medicare is a bigger % of expenses of the avg consumer than reflected by the CPI weight). However, the fed refutes that argument and says that its current measure isn't perfect but neither is the solution proposed.

Currently they are looking at something called the Stock Watson model to see if it provides a better gauge. So by no means is it a settled science.

>Why do people use CPI instead of labor

How would one differentiate real and nominal wage/salary increases?

>housing

Shelter expenditures presently constitute 33.2% of the CPI basket.

>housing or stock prices

Asset prices are only very loosely associated with inflation.

>On a similar note, why would anyone trust the federal reserve's numbers given how the federal reserve has lied in the past?

lol. (Also, BLS calculates CPI, not the Fed.)

CPI is computed by the Bureau of Labor Statistics, not the Federal Reserve. As for why labor, housing, and stock prices aren’t included in the CPI, I would guess because: labor is sticky and are only indirectly related to consumption via pricing, housing is a durable good (people don’t buy it week to week nor does rent change with such frequency), and stock prices don’t affect consumption.

You could make the argument that a better inflation indicator could take these into account, but it wouldn’t be the CPI then.

>...housing is a durable good (people don’t buy it week to week nor does rent change with such frequency),

Rent (and "owner occupied rents") are a part of the bundle used in calculating the CPI.

The owner occupied rent is a calculation of what the rent would be if the owner had paid rent on the house they own. For some background on this:

https://www.philadelphiafed.org/-/media/research-and-data/pu...

Much of what people label as inflation is either what is better known as "Baumol cost disease", or instead the market-distorting effects of near-invisible tax-evading overseas billionaires searching for safe assets and trampling your property market in the process.
What would be a reason for irregular intervals of price registration? Could it be that the pricing changed by McDonalds at this interval and wouldn't the dataset be more complete to include the months in which the price of the Big Mac didn't change?

2000-04-01 2001-04-01 2002-04-01 2003-04-01 2004-05-01 2005-06-01 2006-01-01 2006-05-01 2007-01-01 2007-06-01 2008-06-01 2009-07-01 2010-01-01 2010-07-01 2011-07-01 2012-01-01 2012-07-01 2013-01-01 2013-07-01 2014-01-01 2014-07-01 2015-01-01 2015-07-01 2016-01-01 2016-07-01 2017-01-01 2017-07-01 2018-01-01 2018-07-01 2019-01-01 2019-07-09 2020-01-14

I did use the Big Mac Index to convert the pricing of my SaaS in more than 40 currencies. I did the math in a simple Excel spreadsheet at the time. Will try the data from this repo next time I'll redo the pricing!
I see Argentina's exchange rate is about 60 Pesos per 1 Dollar. While that's not false, the government recently imposed a 30% tax to all foreign currency purchases. So while the exchange rate is 60 the final price you actually pay is 80.

This is assuming you can even buy foreign currency in the first place; people are limited to 200 USD per month.

Things like this is why I'm wary of looking too deeply into "data infographics", especially if they're related to economic statistics. The numbers alone rarely tell the whole story. They're still good for getting the "MBA-level" 30k ft view.