More on Nursing Labor Market

The Health Resources and Services Administration (part of the U.S. Dept. of Health and Human Services) has this to say in regards to nursing supply/demand:

Excerpt:

"An adequate supply of nurses is essential to achieving the Nation’s goals of ensuring access to affordable, high-quality healthcare. The adequacy of nurse supply varies geographically throughout the Nation, with a general consensus that at the national level currently a moderate shortage of registered nurses (RN) exists. The findings of our analysis suggest that the current RN shortage will continue to grow in severity during the next 20 years if current trends prevail and that some States face a more severe shortage than do others. The growth and aging of the population, along with the Nation’s continued demand for the highest quality of care, will create a surging demand for the services of RNs over the coming 2 decades. At the same time, because many RNs are approaching retirement age and the nursing profession faces difficulties attracting new entrants and retaining the existing workforce, the RN supply remains flat."

The current consensus is that the East Coast has a nursing surplus, while the Southwest and West Coast  regions of the U.S. have a nursing deficit.  Why such a huge variation from Coast to Coast?