==== 2024-10-24 ====
Notes from https://www.barrons.com/amp/articles/goldman-sachs-stock-market-lost-decade-9c9fd595
  * the cyclically-adjusted price/earnings ratio uses average trailing 10-year inflation-adjusted earnings
  * CAPE ratio
  * Robert Shiller
    * Nobel Prize-winning economist
    * popularized the CAPE ratio
  * technology and communications services now make up about 40% of the S&P 500