Averaging stock market capitalization to GDP ratios from seventeen developed economies over the past 150 years reveals the world has never witnessed an equity bubble of the current magnitude. The weighted average of seventeen stock market cap to GDP ratios reached 162% at the end of the third quarter of 2021, which is the highest ever since 1870. It’s unlikely it has been higher previous to 1870, because economies were not as intertwined then. Most likely, equity bubbles were more local. In addition, before 1870 countries were commonly on a metallic standard that prevented long periods of excessive speculation.