Dow Jones Ind. Average (Rep./Democr. President)
Data presented in the chart below begins in 1949 with the first full presidential term following WWII to focus on the modern era. First looking at just the historical performance of the DJIA under Democratic and Republican Presidents...
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...we see a pattern that is contrary to popular belief. Under a Democrat, DJIA has performed better than under a Republican. DJIA has historically returned 10.0% under Democrats compared to 6.8% under a Republican executive. Congressional results are the opposite and much more dramatic. Republican Congresses since 1949 have yielded an average 15.3% gain in DJIA compared to a 6.1% return when Democrats have controlled the Hill.
Democrats in power of the two branches have produced an average DJIA gain of 7.4%, below the All Year average gain of 8.3%. With a Democratic President and a Republican Congress or a split Congress, DJIA has performed well averaging a 14.7% gain. The best scenario for all investors has been a Democrat in the White House and Republican control of Congress with average gains of 16.4%.