Importantly, we have not yet seen any sustained pickup in productivity growth. However, given that conditions could shift, it is fair to ask what a higher growth path might mean. As I discussed, it could mean a higher natural interest rate, which would increase the amount of accommodation provided at a given level of the Federal Reserve’s policy interest rate.
12  Kurt Lewin, "The Research Center for Group Dynamics at Massachusetts Institute of Technology," Sociometry, vol. 8, no. 2 (1945): 126-136.