Earnings season is in full swing and we're starting to see the first signs of weakness on the Dow Jones Industrial Average (DJINDICES:^DJI). Most companies to report so far are from the financial, energy, or tech industries, and indications are that they're doing very well.

But quarterly reports from Coca-Cola (NYSE:KO) and Travelers (NYSE:TRV) showed a different story today.

Coca-Cola disappoints
Coca-Cola's earnings of $2.6 billion, or $0.64 per share on an adjusted basis, was slightly ahead of expectations. But in a market in which growth is key Coca-Cola came up short. Revenue fell 1% from a year ago to $12.57 billion, well below the $12.83 billion that Wall Street expected, as the company was hit by major currency headwinds.  

Carbonated drinks like these are falling out of favor for Coca-Cola.

Currency had a negative 11% impact on revenue in Latin America and negative 9% in Eurasia and Africa, so macroeconomic effects were really to blame for the bad second quarter. Volume was even up 3%, driven by noncarbonated beverages -- an area in which Coca-Cola has made a major effort to grow share.

Still, investors weren't excited about the drop in revenue, sending shares down 3.2% in late trading. That's what an earnings miss can do, even if there's fundamental volume growth in the core business.

Travelers brought back to reality
Insurer Travelers has fallen a more worrisome 3.8% after reporting disappointing earnings. Operating profit, which doesn't include some investment results, came in at $1.93 per share for the second quarter, below the Street's $2.07 estimate. Overall, profit was down 26% to $683 million.  

The problem was in part $436 million in catastrophe costs, up from $340 million a year ago, a figure that can vary quarter to quarter. But the broader story is that price increases that were being pushed down to customers have slowed and therefore margin expansion will be curbed as well. Long term, this is part of the ebb and flow of the insurance business, but investors had become accustom to higher margins and we may be seeing them peak for Travelers.

In addition, the 2nd U.S. Circuit Court of Appeals in New York today found that Travelers must pay $500 million for asbestos-related claims. This dates back to the coverage of Johns-Manville, which declared bankruptcy in 1982 because of asbestos-related costs.

Foolish takeaway
While these two earnings reports weren't good for investors, they weren't reason to panic, either. Coca-Cola's volumes are growing, which is great for the company over the long term, and Travelers was still highly profitable despite some higher than usual costs in the quarter. These ups and downs will even out over time, something long-term investors need to keep in mind.