Sept. 23 (Bloomberg) — Pennsylvania's general-obligation rating was cut to the lowest since 1997 by Fitch Ratings, which cited a reliance on one-time revenue fixes and growth in costs such as pensions.

Fitch reduced the rating one step to AA-, its fourth- highest level. In July, Moody's Investors Service lowered its grade to an equivalent Aa3, also pegging the cut to mounting liabilities for the sixth-most populous state. Standard & Poor's grades it AA, third highest.

"Pennsylvania faces fiscal pressures in the form of a structurally unbalanced budget, depleted reserves and a rapidly growing pension cost burden following years of underfunding and market-driven investment declines," Fitch analysts led by Eric Kim said in a release today.