Stocks rose at market open Wednesday as an unexpected increase in producer prices showed inflation pressures beginning to subside, a positive sign for the U.S. economy.br The S&P 500 added 0.79, the Dow Jones Industrial Average was up 0.65, and the Nasdaq jumped 0.9.br Producer prices unexpectedly rose in January, up 0.1 compared to an expected 0.2 decline.br Core prices, excluding volatile items such as food and energy, rose 0.2 and are up 0.8 over the past 12 months.br The reading proves a positive for inflation which has been weighed down by a slump in commodity prices.br Industrial production in the U.S. climbed 0.9 in January, three times the increase analysts had expected.br Sharper growth indicated fears over the health of the U.S. economy, particularly in manufacturing, may have been overblown.