(Bloomberg) -- U.S. equity futures dropped and European stocks fell to a three-week low on the busiest earnings day of the season.

Apple Inc., Amazon.com Inc., Alphabet Inc. and Facebook Inc. fell in pre-market trading. United Parcel Service Inc. jumped on a surge in delivery demand during the pandemic. Qualcomm Inc. rallied after giving a strong sales forecast.

All eyes today will be focused on the biggest American tech giants, which are due to release earnings after markets close. The U.S. economy suffered its sharpest downturn since at least the 1940s in the second quarter, according to the Commerce Department’s initial estimate.

In Europe, the DAX Index fell the most in a month after data showed Germany’s economy plunged into a record slump in the second quarter.

Gold dropped for the first time in 10 days while the dollar edged higher. Two-year Treasury yields are about two basis points away from falling below the record set in May.

Apple, Amazon.com, Alphabet and Facebook now have an unprecedented level of influence in the U.S. stock market after investors bid them up during the pandemic-induced recession. Along with Microsoft Corp., they make up 22% of the S&P 500.

“Tonight could be a pivot for markets with four of the big tech companies reporting earnings,” said Berndt Maisch, a senior portfolio manager at Tresides Asset Management. “Their stocks are so super expensive and hence offer very little room for any disappointment. Should they miss the high expectations that could lead to a significant market shake up. We can already see that nervousness within European markets today.”

Also in the backdrop are ongoing worries about the health of the global economy as the pandemic rages in many U.S. states. In Germany, new coronavirus cases have spiked to the highest in about six weeks.

“Markets are nearing their limits without further stimulus and a much stronger recovery,” said Andrew McCaffery, the global CIO of asset management at Fidelity International, citing the failure to get the outbreak under control in some countries. “The third quarter is likely to be much more challenging and markets could see renewed volatility.”

Here are some key events coming up:

• Apple, Amazon.com, Alphabet report earnings after the close on Thursday; results from Chevron Corp. and Caterpillar Inc. are due Friday.
• U.S. second-quarter GDP is due on Thursday.
• China PMI data comes Friday.

These are some of the main moves in markets:

Stocks

• Futures on the S&P 500 Index fell 0.8% as of 8:38 a.m. New York time.
• The Stoxx Europe 600 Index declined 1.4%.
• Germany’s DAX Index sank 2.6%.
• The MSCI Asia Pacific Index decreased 0.2%.

Currencies

• The Bloomberg Dollar Spot Index jumped 0.3%.
• The euro decreased 0.3% to $1.1754.
• The Japanese yen weakened 0.3% to 105.19 per dollar.
• The British pound climbed 0.2% to $1.3022.

Bonds

• The yield on 10-year Treasuries dipped two basis points to 0.55%.
• Germany’s 10-year yield decreased five basis points to -0.55%.
• Britain’s 10-year yield decreased four basis points to 0.079%.

Commodities

• West Texas Intermediate crude fell 1.6% to $40.62 a barrel.
• Gold weakened 1% to $1,951.32 an ounce.

©2020 Bloomberg L.P.