PITTSBURGH — A Democrat running for governor in Pennsylvania wants to add a 5 percent tax to the shale gas drilling boom.

U.S. Rep. Allyson Schwartz says in a Wednesday release that the rate would still be lower than the 7.5 percent tax Texas charges.

Schwartz says the tax could generate $13 billion in revenue over a decade from Pennsylvania's Marcellus Shale, which also extends under Ohio, West Virginia and New York.

Pennsylvania doesn't currently tax gas production, but Republican Gov. Tom Corbett and legislative leaders created an impact fee last year that charges drillers for each well, and companies also pay corporate taxes. Experts say the impact fee is the equivalent of about a 1.5 percent tax.

WASHINGTON — Average fixed rates on U.S. long-term mortgages neared their highs for the year this week amid signs of further strength in the economy.Mortgage buyer Freddie Mac said Thursday that the average rate on the 30-year loan was 4.57 percent this week. That's up from 4.51 percent last week and close to the high this year of 4.58 percent reached Aug. 22.The average on the 15-year fixed mortgage rose from 3.54 percent to 3.59 percent. That's near the year's high of 3.6 percent.

WASHINGTON — U.S. workers were more productive from April through June than previously estimated while labor costs were unchanged.Productivity grew at an annual rate of 2.3 percent in the April-June quarter, up from an initial estimate of 0.9 percent growth, the Labor Department said Thursday. Unit labor costs were flat in the second quarter, less than the 1.4 percent rise the government had initially estimated.The combination of stronger productivity and less of an increase in wages should provide assurances to the Federal Reserve that inflation is not a threat.

NEW YORK — Americans’ cautious spending on clothing extended into August, capping a weak back-to-school selling season for retailers.Several retailers including clothiers Cato and L Brands on Thursday posted disappointing revenue during the month, which falls in the middle of the second biggest shopping period of the year.The results raise questions about whether Americans will spend during the winter holidays in November and December, a time retailers can make up to 40 percent of their revenue for the year. While the back-to-school season, which runs from mid-July through mid-September, isn’t an absolute predictor of how Americans will spend during the winter holidays, it does offer insight into consumers’ mindset.Benchmark oil for October delivery gained $1.14, or 1.1 percent, to close at $108.37 a barrel on the New York Mercantile Exchange. Brent, the benchmark for international crudes, was up 18 cents to $115.09 a barrel on the ICE Futures exchange in London.Natural gas futures fell 10.8 cents, or 2.9 percent, to $3.575 per 1,000 cubic feet.