Objective research to aid investing decisions

Value Investing Strategy (Strategy Overview)

Allocations for August 2020 (Final)

Momentum Investing Strategy (Strategy Overview)

Allocations for August 2020 (Final)
1st ETF 2nd ETF 3rd ETF

Party in Power and Stock Returns

| | Posted in: Political Indicators

Past research relating U.S. stock market returns to the party holding the Presidency mostly concludes that Democratic presidents are better for the stock market than Republican presidents. However, the President shares power conferred by the electorate with Congress. Does historical data confirm that Democratic control of Congress is also better for stock market returns than Republican control of Congress? Is control of the smaller Senate more decisive than control of the House of Representatives? To check, we relate annual U.S. stock market (S&P 500 Index) returns to various combinations of party control of the Presidency, the Senate and the House of Representatives. Using party in power data and annual levels of the S&P 500 Index for 1950 through 2017 (68 years), we find that:

The following chart summarizes average calendar year S&P 500 Index returns for various combinations of party in power over the full 68-year sample period. The number in parentheses after each combination is the number of years during which the combination holds. Some subsamples are extremely small. Results broadly suggest that stocks do better when Democrats (Republicans) control the Presidency (Congress).

Various combinations suggest that Republican control of the Senate may be most decisively favorable for U.S. stocks, with:

  • Average performance strong when Republicans control the Senate.
  • Outperformance (underperformance) under Democratic (Republican) presidents associated with Republican (Democratic) control of the Senate.

Using “election year” (November through October) returns rather than calendar year returns makes little difference.

In summary, evidence from a limited sample suggests that Republican control of the Senate may be the most decisively favorable party-in-power indicator for U.S. stocks.

Cautions regarding findings include:

  • As noted, subsamples are small for reliable inference.
  • The margins of power in the Senate and House of Representatives may be factors, but the small sample/subsample sizes argue against further stratification.
Daily Email Updates
Filter Research
  • Research Categories (select one or more)