From Preschool to Prosperity: The Economic Payoff to Early Childhood Education

Source: Timothy J. Bartik, Upjohn Institute, September 2014

From the summary:
Bartik shows that investment in high-quality early childhood education has several long-term benefits, including higher adult earnings for program participants.
Why Early Childhood Education is an Attractive Economic Development Investment
Source: Timothy J. Bartik, W.E. Upjohn Institute for Employment Research, Presentation at webinar of ReadyNation and Council of State Chambers Policy Center, September 16, 2014