It was a seesaw battle this week for stock markets, and in the end we pretty much ran in place. The Dow Jones Industrial Average (DJINDICES:^DJI) fell just 0.12% for the week but fell below the 14,000 level, where we ended last week, and the S&P 500 (SNPINDEX:^GSPC) was up 0.25%. This wasn't a week for major economic news, but a trade report on Friday showed some signs of life for the economy. The U.S. trade deficit fell 21% in December to $38.5 billion, driven by a decrease in oil imports. It's probable now that GDP didn't drop in the fourth quarter, and revisions will show slight growth through all of 2012.

Shares of UnitedHealth Group (NYSE:UNH) were the biggest gainers on the Dow this week, climbing 3.5%. All of that gain occurred on Tuesday, after Goldman Sachs increased its rating on the stock from neutral to buy. Analysts' price target was bumped up to $66 from $57 on a prediction that earnings would grow through 2014. This is the latest sign that investors don't think the health-care bill will be all bad for insurers.

Coca-Cola (NYSE:KO) jumped 3.3% this week, ahead of the company's earnings report on Tuesday. The driver this week was likely a slightly stronger-than-expected earnings report from customer Coca-Cola Enterprises and also a stronger-than-expected outlook. The company reported strong pricing despite weak demand in Europe and sales grew 1%, while earnings per share of $0.45 beat estimates by a penny, but investors were excited to see a prediction of mid-single-digit sales growth next year. Coca-Cola doesn't have a stake in CCE, but it does own some of its own bottling business in North America, and this could be an indicator that results going forward will be stronger than expected.

Shares of American Express (NYSE:AXP) rounded out the top three with a 3.2% gain for the week. CEO Kenneth Chenault gave some more detail about 2012's results at a conference, revealing that international growth for the year was 2% to $9.3 billion. The Federal Reserve also reported that consumer borrowing rose $14.6 billion in December to the highest level on record. This is great news for credit card companies like American Express that extract fees and interest when consumers use their cards.