What are some facts about U.S. state bond ratings?

Facts about state bond ratings include that North Dakota and Texas have AAA ratings with Standard and Poor's due to oil booms, and S&P downgraded New Jersey's rating to AA- due to overly optimistic forecasts in 2014, according to the Pew Charitable Trusts. California earned a "positive" rating in 2014.

Missouri, North Carolina and Virginia have had AAA ratings with S&P for 50 years or more, notes the Pew Charitable Trusts. Massachusetts diversified its economy to increase its rating from AA- to AA+ between 2001 and 2014. Alaska increased its rating from AA to AAA between 2003 and 2014 by conservatively managing its oil money.