Anyone know what those signals are? A lot of 'end is nigh' articles I've read have more details. Is it just too much growth in the stock market? Debt? Speculation?
Keep an eye on total consumer debt levels, and more importantly debt-to-income. We've already surpassed the absolute peak value of consumer debt load from 2008 [0], but debt-to-income is still ok for now. When that starts to change we're probably in trouble.
[0] http://www.businessinsider.com/americas-consumer-debt-keeps-...
[0] https://www.bloomberg.com/news/articles/2018-04-18/from-citi...
[1] https://www.bloomberg.com/news/articles/2018-07-20/trump-bla...
[2] https://fred.stlouisfed.org/series/T10Y2Y/
[3] https://wolfstreet.com/2018/07/05/as-the-yield-curve-flatten...
[4] https://www.federalreserve.gov/econres/notes/feds-notes/dont...
As I understand it, the theory basically goes like this: Low unemployment leads to higher labor costs, which leads to wealthier workers and higher demand for products, which leads to even higher demand for labor. Essentially a positive feedback loop of inflation, which the Fed will stop by increasing interest rates. They may notice too late, or be late deliberately, and thus have to raise interest rates a lot and fast.
The stock market is currently 43% more overvalued than just prior to the 2008 financial crisis and 14% more overvalued than the height of the 2000 dotcom bubble.