A poorly-received set of results from iron ore pellet producer Ferrexpo and a surprise contraction in the world's largest economy saw the industrial metals and mining sector slump into the red on Wednesday.Ferrexpo was 5.59% lower at 256.7p in afternoon trade after seeing profits slump in the first nine months of the year as falling prices and demand were met with rising costs.The firm said that the average benchmark iron fines price had fallen from $177 per tonne to $131 per tonne, while sales fell from 7.2m tonnes in 2011 to 7.0m tonnes. Nickel- and zinc-focused producer Talvivaara was trading 3.28% lower at 95.75p today after JPMorgan Cazenove downgraded its rating for the stock to 'underweight'.The US bank said that "we think the company's ability to avoid a dilutive fundraising is rapidly diminishing".The wider metals and mining sector, including sector peers Bellzone Mining and EVRAZ, was firmly out of favour today as it was revealed that the US economy contracted by 0.1% in the fourth quarter of 2012, disappointing analysts who had expected a 1.1% expansion. This was also a sharp contrast to the 3.1% growth registered in the third quarter, sparking worries about the demand outlook for commodities.Top performing sectors so far todayTechnology Hardware & Equipment 1,061.93 +1.40%Fixed Line Telecommunications 2,931.32 +0.98%Media 5,101.06 +0.79%Personal Goods 21,520.78 +0.63%Health Care Equipment & Services 4,140.51 +0.40%Bottom performing sectors so far todayIndustrial Metals & Mining 3,017.47 -3.55%Oil Equipment, Services & Distribution 24,947.14 -3.13%Tobacco 36,669.79 -2.10%Chemicals 8,932.62 -1.91%Construction & Materials 3,715.78 -1.38%BC