Here is a good example of why I prefer to grasp an understanding of demographic and social change rather than some dumbed down rule of 70.
Demographics key to understanding interest rates
“Step back from the IMF forecasts of lower growth and low interest rates and we see a fundamental change taking pace in developed countries, including Australia and the US. And, because this change is linked to lower population growth rates, it will last for decades and will create boom and bust industries that will distort economic patterns and share markets.”
https://www.theaustralian.com.au/business/economics/demographics-key-to-understanding-interest-rates/news-story/3a657cc28dc262f7dc100902a7cabd05
