> Do note that peak spending on rail roads eventually amounted to ~20 percent of the US GDP in the 19th century.

Has anyone found the source for that 20%? Here's a paper I found:

> Between 1848 and 1854, railroad investment, in these and in preceding years, contributed to 4.31% of GDP. Overall, the 1850s are the period in which railroad investment had the most substantial contribution to economic conditions, 2.93% of GDP, relative to 2.51% during the 1840s and 2.49% during the 1830s, driven by the much larger investment volumes during the period.

https://economics.wm.edu/wp/cwm_wp153.pdf

The first sentence isn't clear to me. Is 4.31 > 2.93 because the average was higher from 1848-1854 than from 1850-1859, or because the "preceding years" part means they lumped earlier investment into the former range so it's not actually an average? Regardless, we're nowhere near 20%.

I'm wondering if the claim was actually something like "total investment over x years was 20% of GDP for one year". For example, a paper about the UK says:

> At that time, £170 million was close to 20% of GDP, and most of it was spent in about four years.

https://www-users.cse.umn.edu/~odlyzko/doc/mania18.pdf

That would be more believable, but the comparison with AI spending in a single year would not be meaningful.

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theologic 7 days ago | parent | next [-]

By the way it's always nice when somebody actually tries to double check somebody else's research especially when you hear numbers that seemingly just sound crazy. Maybe another factoid, GDP or GNP for all practical purposes wasn't rigorously done by the government until about 1944. I believe a large part of our viewpoints on what happened in the 1800s is primarily based upon census data. But obviously if you're trying to measure a 7 year event Using census that happens every 10 years, there's going to be a lot of gap in the whisker chart.

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potato3732842 7 days ago | parent [-]

Is 20% on railroad actually crazy? We spend 20% on make-work for the healthcare industry.

In a majority agrarian economy where a lot of output doesn't go toward GDP (e.g. milking your own damn cow to feed milk to your own damn family won't show up) I would expect "new hotness" booms to look bigger than they actually are.

	▲	shakezula 6 days ago \| parent [-]
		I definitely think 20% is not that crazy, especially considering the gains those railroad investments are probably still paying to this very moment.

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Onewildgamer 7 days ago | parent | prev [-]

So we're much closer to the per year spend US saw during the railroad construction era.

At this rate, I hope we get something useful, public, and reasonably priced infrastructure out of these spending in about 5-8 years just like the railroads.