Share prices collapsed in the Great Depression, but again did not return to the pre-Depression peaks until the mid-1960s, suggesting again the possibility that a bubble 3 had developed in the earlier period. Finally, we consider the airline industry. After Lindbergh's 1927 transatlantic flight, airline stocks soared, and many companies rushed into the business.
Although we altered our neutral policy rate assumption, we made no change to our assumption about the neutral interest rate faced by households and businesses.