clipped from: lewrockwell.com   
A Decade Of Vitamin D Supplementation Would Save $4.4 Trillion Over A Decade; Would Save $1346 Per Person Per Annum
by Bill Sardi
Health demographers guesstimate that if human populations in Northern Europe were to achieve adequate vitamin D3 levels (40 nanograms per milliliter of blood sample) this would save 17.7% in direct and indirect healthcare costs, saving hundreds of billions of dollars/Euros per year.
If these Northern European statistics can be extrapolated to the United States, the U.S. would save about $4.4 trillion in healthcare costs over the next decade.

Such an extrapolation cannot be cleanly made since Northern Europe exists in a less sunny climate where far less vitamin D is produced, particularly in winter months; however, vitamin D deficiency is widely reported even in sunny climates such as Florida.