The stock market suffered significant losses on Tuesday, with the Nasdaq Composite (^IXIC 0.63%), Dow Jones Industrial Average (^DJI 0.62%), and S&P 500 (^GSPC 0.55%) all losing more than 1%. Wall Street seemed nervous about volatile trading in regional bank stocks, and anxiety about what the Federal Reserve will say about interest rates when its two-day meeting concludes on Wednesday also weighed on market sentiment.

Index

Daily Percentage Change

Daily Point Change

Dow

(1.08%)

(367)

S&P 500

(1.16%)

(48)

Nasdaq

(1.08%)

(132)

Data source: Yahoo! Finance.

After the closing bell, Advanced Micro Devices (AMD -0.18%) and Starbucks (SBUX 2.09%) were among those companies reporting their latest financial results. The numbers that the two well-known businesses released were somewhat disappointing for shareholders and resulted in significant declines in share prices after hours. Below, you'll learn more about what caused shares of AMD and Starbucks to move downward.

1. AMD sees a big pullback in chip sales

Shares of Advanced Micro Devices were down almost 7% in after-hours trading Tuesday evening. The semiconductor manufacturer's first-quarter financial results were better than some had feared, but they still didn't allay concerns about sluggishness across the industry, and an uncertain outlook weighed on investor sentiment.

It was easy to understand why many investors weren't all that excited about AMD's results. Revenue was down 9% year over year to $5.35 billion, and gross margin figures dropped between three and four percentage points. AMD posted a modest loss, and even after accounting for extraordinary items, adjusted net income of $970 million was down 39% from year-ago levels and worked out to adjusted earnings of just $0.60 per share.

AMD's segments showed disparate performance. Embedded chips grew dramatically, with segment revenue climbing 163% and operating income nearly tripling from year-ago levels. Yet, flat sales in the data center segment accompanied a 65% drop in operating income, and big declines in the client segment weighed on overall performance. Modest drops in the gaming segment also didn't help matters.

In addition, AMD doesn't expect to see much of a pickup heading into the spring. Second-quarter guidance called for revenue of between $5 billion and $5.6 billion, which would imply flat to slightly lower sales for the chipmaker. That's not the upbeat outlook that most investors wanted to see from AMD.

2. Starbucks cools off

Shares of Starbucks also fell after hours, dropping 5%. The coffee giant's fiscal second-quarter results for the period ended April 2 were better than many had expected but weren't enough to forestall a share-price decline.

Starbucks' fundamental performance looked good. Revenue climbed 14% year over year to $8.7 billion, helped by an 11% rise in global comparable store sales. Starbucks enjoyed growth in both traffic and average spending per transaction, and even the tough Chinese market gave the company a 3% rise in comps. The company also opened 464 net new stores during the quarter. Adjusted earnings of $0.74 per share rose 25% from year-ago levels and also came in better than most projections among those following the stock.

Yet many seemed disappointed that Starbucks remained subdued about its guidance for the remainder of the year. In particular, the company expects the big bounce in China to diminish in the second half of the fiscal year, and there's still considerable uncertainty about the impact of macroeconomic conditions on growth.

Starbucks remains the giant of the coffee industry, but it still has to be cautious about competition and other challenges. If it doesn't keep executing well, then its stock could remain under pressure.