Based on research by Newell and Pizer, the text suggests the two following time-declining rate schedules, the first based on the social marginal rate of time preference and the second based on the optimal growth rate model;

 

Year

pz

px

0 - 50

1.5 percent

3.5 percent

50-100

1.0 percent

2.5 percent

100-200

0.5 percent

1.5 percent

200-300

0.0 percent

0.5 percent

Over 300

0.0 percent

0.0 percent