GDP in the United States was $16,150 billion in 2012, and $19,400 billion in 2017. Over that same five years, population rose from 314 million people to 326 million, and prices rose by a total of 7.8%. The average annual rate of real per-capita growth from 2012-2017 was:

a) 1.0%

b) 1.4%

c) 1.5%

d) 2.1%

e) 7.3%