Mars synodic cycle - Cosmic "stress test"

Mars synodic cycle has been always of special interest for me. I liked to watch it in regards to different events. And only dramatic events of the fall and winter of 2008 - 2009 finally gave me some ideas how this cycle might work. 

Let's calculate a composite diagram for the Sun-Mars geocentric cycle in regards to Dow Jones Industrial Index (I use the data from the year 1885). This is how it looks like:

There is nothing interesting here except those two big drops around the conjunction. One drop took place one month before Sun-Mars conjunction, and another happened 3-4 months after the conjunction. All other periods of this cycle practically do not affect the stock market; only the periods around the conjunction (a month before and 3-4 months after) do. 
Watch how this cycle is working now (a red curve):

All big drops of 2008-2009 year are perfectly described by this cycle.

I would like to compare this cycle with a tax man. Most of the time we do not think about that guy; he comes in due time, and this is unavoidable.

We can assume that our "tax man" whose name is "Mars synodic cycle" comes to inspect the World Economy once in 2 years and 2 months (Mars's synodic cycle has a period of 780 days). The guy applies the charges (i.e., drops of the market) around the Sun - Mars conjunction. First time it happens a  month before the conjunction, and then it is repeated several months (3-4) after. The composite diagram above simply confirms this fact. All other times the World Economy is not affected by this guy.

Good news is that this guy comes to inspect the World Economy not every 2 years; sometimes it skips the visit. 

Let's look how this cycle has worked  in the past:

The nearest Sun-Mars conjunction took place in the year 2006; Dow was not affected at all:

In 2004, it has had some impact on Dow:

In 2002, this "tax man" inspected Dow very attentively:

No affect revealed in 1991, 1994, 1996, 1998, and 2000. Maybe, there was nothing to inspect.

In 1987 it worked this way:

In 1974-1975:

In 1947:

In 1927:

Definitely, this cycle is not the only one responsible for significant drops of the market. (To find other guys, try to conduct a research of similar drops.) However, I would suggest to keep it in mind: if it intends to affect the market, it gives signs several months ahead - similar to tax agencies that send forms and notices a way before the taxation period.