I point The income of college graduates is 70,000 before tax and 65,000 after tax Secondary school graduates earn 60,000 before tax and 55,000 after tax . College graduates spent 3 years in college and did not work for this period. The private costs of going to college are 10,000 in total after any subsidies from the government. The students receive 3,000 in back to education subsidies from the government. There are positive externalities from college education of 3,000. Estimate the social rate of return on education