Tesla hit record high on last day of trading before joining S&P 500

Dec. 18 (UPI) -- Tesla's shares rose 6% to a record high of $695 at close Friday, the last day of trading before it joins the S&P 500 index.

The company owned by Elon Musk will be the largest ever added to the S&P 500, with a market capitalization of $650 billion.

The index slipped to 3,709.41, down 0.35% ahead of the major addition. For the week, the S&P 500 finished up 0.37%.

The Dow Jones Industrial Average also fell Friday, closing at 30,179.05, down 0.41%. The index was down 0.33% for the week.

And the tech-heavy Nasdaq Composite lost about 0.71% to close at 12,755.64. The index was up 1.84% for the week.

The lackluster Friday finishes is likely linked to Congress' struggles coming to an agreement on a new pandemic-related stimulus plan.

Congressional negotiators are hoping to attach a COVID-19 relief bill worth about $900 billion onto a $1.4 trillion measure to fund federal government operations through September. They're facing a Friday deadline for the latter.