Why are USA used vehicle prices rising so fast?
Here is a foreign article that makes a strong argument that it is not just a shortage of chips for new vehicles,
but that prices in general are rising sharply (inflation) due to “the big picture” of world trade, especially USA and mainland China:

https://asiatimes.com/2021/07/will-china-bail-out-biden/

Warning: it is a long read.

sample quote

But Jin adds: “Now the United States has issued a massive amount of excess currency due to the epidemic, and the amount of currency issuance far exceeds the normal needs of economic development, so there is a situation in which more currency is issued but production cannot be restored. Inflation in the United States is rising, which will put a lot of pressure on the US finances. The US federal debt is approaching $30 trillion.

“What does this imply? At present, the interest on US Treasury bonds is more than 1% point, and the annual interest payment is about $300 billion US dollars, which is considered to be affordable. But if inflation approaches 5% or even exceeds 5% (interest rates will definitely follow after inflation exceeds 5), then the United States will need $1.5 trillion a year to repay the interest of 30 trillion federal treasury bonds, which will definitely lead to the bankruptcy of the government.”

Jin continued: “So the United States is actually looking to China now. You may have noticed that in the past, the United States has always said that China manipulated the RMB ( “Yuan” ) exchange rate and artificially lowered the RMB exchange rate. However, recently, the tone of the United States has completely changed… Why don’t you ask for appreciation? Because our things become more expensive as soon as the renminbi appreciates, and the United States must import our goods, and that adds to inflationary pressure.”

Treasury Secretary Janet Yellen said some weeks ago that tariffs on Chinese goods had hurt American consumers, Jin noted, adding that “it is very likely that Yellen will cancel the tariffs imposed on China within this year.”

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