… is from page 3 of William Baumol’s useful 2002 volume, The Free-Market Innovation Machine  (original emphasis):
Average growth rates for about one and a half millennia before the Industrial Revolution are estimated to have been approximately zero, and, although there was undoubtedly some growth starting around the tenth century, it proceeded at a snail’s pace by modern standards. Even the most well-off consumers in pre-Industrial Revolution society had virtually no goods at their disposal that had not been available in ancient Rome…. In contrast, in the past 150 years, per capita incomes in a typical free-market economy have risen by amounts ranging from several hundred to several thousand percent.
Non-economist readers should be made aware that Baumol  is a very well-respected, wide-ranging economist (now at NYU) and hardly one who is regarded by his fellow economists as being ideologically biased toward laissez-faire.