Over the past month we've seen that the Dow Jones Industrial Average (DJINDICES:^DJI) has been acting a little weird when we compare it with the previous six months.

During 2013, the Dow has closed higher or lower by more than 100 points 41 times. In January it was just once -- Jan. 2, when the Dow rose 308 points. In February, it happened seven times, in March twice, April seven times, May eight times ... and then 16 times in June.

Moreover, since May 28, the Dow has had 19 days in which it closed higher or lower by more than 100 points. That's 19 out of 24 trading sessions. And within that time period, there haven't been two consecutive days in which the index didn't close higher or lower by more than triple digits. Furthermore, of the five days in which the Dow didn't end the day with a 100-point move, on only two of those days -- June 10 and May 30 -- did the index experience a trading range in which at one point during the day the Dow wasn't higher or lower by more than 100 points. But even on one of those two days, May 30, the Dow was up 95 points at one time.

Day

Previous Day's Close

Day's High

Day's Low

Days Close

Change for Day

Intraday High

Intraday Low

June 21

14,760.62

14,858.56

14,688.43

14,799.40

41.08

100.24

(69.89)

June 10

15,248.12

15,300.64

15,211.25

15,238.59

(9.53)

52.52

(36.87)

June 6

14,960.59

15,040.62

14,844.22

15,040.62

80.03

80.03

(116.37)

June 4

15,254.03

15,304.98

15,100.78

15,177.54

(76.49)

50.95

(153.25)

May 30

15,302.80

15,398.70

15,280.99

15,324.53

21.73

95.90

(21.81)

Data from Yahoo Finance and author's calculations.

From June 11 to June 20, an eight-day streak, the index ended every day up or down more than 100 points. It did the same just this past week -- June 24 through the 28th. Before June 11, the Dow's longest streak had been four days back in February -- the 22nd to the 27th -- and had three consecutive 100-point moves: once in April (the 15th through the 17th) and again in May (the 1st to the 3rd).

The consecutive 100-point moves by the Dow over the past few months and the recent string of triple-digit moves in June all have one common occurrence preceding the moves: a Federal Reserve-related event -- either a two-day meeting or the release of its previous meeting's minutes.

The Fed has met four times thus far in 2013 and released minutes from three of the four.

Date of Meeting

Jan. 29-30

March 19-20

April 30-May 1

June 18-19

Date of Minutes Release

Feb. 20

April 10

May 22

N/A

Data pulled from The Federal Reserve.

Based on the Fed's minutes release dates in February and April, the Dow reacted with a string of big changes within two days after those events, and then the three-day 100-point move in May followed the central bank's two-day meeting, which ended the first of a three-day, 100-point change. While we only had one Federal Reserve event in June, most market participants would claim that the May 22 minutes caused interest rates to begin rising along with a massive wave of uncertainty about what the Fed was planning to do with its stimulus programs. And as well all know, there is nothing investors dislike more than uncertainty.  

Final thoughts
Because of how the Dow's big moves correlate with the Federal Reserve and the recent string of 100-point moves in June, I think it's pretty safe to say that investors are probably in for a wild second half of the year. Until the Fed actually makes a move to either slow its stimulus programs or sets a hard date to do so, the uncertainty will continue to move about the market and cause the big point swings.

As individual investors, we shouldn't be frightened away by this volatility. We should embrace it and see it as a great buying opportunity. As the Dow slides lower and individual companies are pulled into the red by these macro events, we can take advantage of quality stocks selling at discounts.

Fool contributor Matt Thalman owns shares of Apple, Google, Amazon.com, and Facebook. Check back Monday through Friday as Matt explains what caused the Dow's winners and losers of the day, and every Saturday for a weekly recap. Follow Matt on Twitter @mthalman5513.

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