For example, as shown in Figure 3.10, US mail volume increased for decades upon decades until the 1990s. And it started to level off in the 1990s (forming an S shape from 1926 to 1999) with the rise of email and the Internet, and then, since the early 2000s has fallen off a cliff (the beginning of a reverse S). Nobody today expects the number of letters delivered to rise in a decade's time. This same pattern could confront the conventional automobile as we know it today. From Levinson and Krizek (2015) The End of Traffic and the Future of Transport. http://davidlevinson.org/the-end-of-traffic-and-the-future-of-transport/  Figure 3.10 Source: US Postal Service (nd) Pieces of Mail Handled, Number of Post Offices, Income, and Expenses Since 1789.  https://about.usps.com/who-we-are/postal-history/pieces-of-mail-since-1789.htm.