Stocks fell on Monday as market participants took a step back to digest valuations following last week's record-setting rallies and looked towards the potential impacts of additional U.S. fiscal stimulus in response to the pandemic. Traders also began to focus on the fallout from the political unrest in Washington as House Democrats draw up articles of impeachment towards President Donald Trump.

Over the weekend, House Speaker Nancy Pelosi announced that the House of Representative will push for Trump's impeachment if Vice President Mike Pence and the Trump administration's cabinet do not invoke the 25th Amendment of the U.S. Constitution to remove Trump from his position. At this time, Pence does not have any intention to remove Trump.

Here's how the market settled to open the week:

S&P 500 Index (SPY  ): -0.66% or -25.07 points to 3,799.61

Dow Jones Industrial Average (DIA  ): -0.29% or -89.28 points to 31,008.69

Nasdaq Composite Index (QQQ  ): -1.25% or -165.54 points to 13,036.42

For Stocks, Twitter (TWTR  ), Facebook (FB  ), Snapchat (SNAP  ) and Shopify (SHOP  ) came under criticism on Monday, with Twitter taking a brunt of the heat, after the internet platforms suspended accounts associated with President Donald Trump's personal accounts following last week's unrest at the U.S. Capitol. Additionally, Amazon (AMZN  ), Apple (AAPL  ) and Google (GOOGL  ) came under early antitrust pressure after the tech giants banned the social media app Parlor from their platforms.

For Sector Performance, sectors on the S&P 500 ended Monday's session mostly negative, with only Energy (XLE  ), Health Care (XLV  ), and Financials (XLF  ) posting positive gains. The session's biggest losers were Consumer DIscretionary (XLY  ), Communication Services (XLC  ) and Real Estate (XLRE  ) falling over 1%.

For Commodities and Currencies, the U.S. Dollar (UUP  ) rose higher on Monday, strengthening from the continued spike in U.S. Treasury yields and global economic growth bets on additional U.S. pandemic stimulus. The dollar index, which tracks the greenback against global currencies, climbed 0.4% higher at 90.636. Bitcoin fell nearly 20% on Monday before paring some losses, marking the digital currency's worst one-day drop since March and wiping $200 billion the cryptocurrency market as other cryptos fell in tandem. Gold (GLD  ) slipped on Monday as the increasing dollar and higher U.S. Treasury yields. Spot gold fell 0.1% to $1,846.72 per ounce, while U.S. gold futures settled 0.7% higher at $1,848.70 per ounce. Crude oil futures left Monday's session with little changed as renewed global lockdown measures weighed on demand outlooks but the stronger U.S dollar kept loses prices in check. International benchmark Brent Crude (BNO  ) dipped 0.6% lower at $55.66 per barrel, while domestic benchmark West Texas Intermediate (USO  ) remained relatively unchanged at $52.25 per barrel.

For Tuesday, market participants will turn their attention to developing impeachment hearings towards President Donald Trump in the wake of civil unrest at the U.S. Capitol last week. Data on November job openings are also scheduled to be released.