# Computing the Dow Jones Industrial average for 06-05-2009.

**URL:** <https://boards.straightdope.com/t/computing-the-dow-jones-industrial-average-for-06-05-2009/498913>\
**Category:** Factual Questions\
**Created:** [June 6, 2009, 7:18am UTC](https://boards.straightdope.com/t/computing-the-dow-jones-industrial-average-for-06-05-2009/498913 "2009-06-06T07:18:17Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![wolf\_meister](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolf_meister/32/15202_2.png) [@wolf\_meister](https://boards.straightdope.com/u/wolf_meister)\
**Post date:** [June 6, 2009, 7:18am UTC](https://boards.straightdope.com/t/computing-the-dow-jones-industrial-average-for-06-05-2009/498913/1 "2009-06-06T07:18:17Z")

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As of June 8, 2009, two stocks (General Motors and Citigroup) will no longer be in the Dow 30 and their replacements will be Cisco Systems and Travelers. Because of this, I decided to calculate the Dow Jones Industrial Average since the [Dow Divisor](http://en.wikipedia.org/wiki/DJIA_divisor) will change as of June 8, 2009. (Yes, I’m working on this for my website).  
Anyway, to calculate the DJIA, you add up the closing prices for the 30 stocks, and divide it by the previously mentioned [Dow Divisor](http://en.wikipedia.org/wiki/DJIA_divisor).  
Anyway, the closing prices sum to 1,100.24 and the divisor is currently reported as 0.125552709. Dividing the sum by the Dow divisor we get 8,763.17… but the DJIA reported for the stock exchange closing of June 5, 2009 is 8,763.13.  
I know this amounts to a “whopping” 4¢ difference but since this is the Dow Jones Industrial Average, shouldn’t it be _exactly_ the same as what I calculated?

Pursuing this further, it seems for the Dow average to come to 8,763.13 the 30 stock total has to be lower by .005 ¢ - yes a half of one cent.

Anyway, does anyone have any ideas about this?

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**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\
**Post date:** [June 6, 2009, 8:39am UTC](https://boards.straightdope.com/t/computing-the-dow-jones-industrial-average-for-06-05-2009/498913/2 "2009-06-06T08:39:29Z")

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How are the stock values reported? To what fraction of a cent?

> [@wolf\_meister](#):
>
> Pursuing this further, it seems for the Dow average to come to 8,763.13 the 30 stock total has to be lower by .005 ¢ - yes a half of one cent.

0.005 cents? Don’t you mean 0.005 _dollars?_

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**Author:** ![wolf\_meister](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolf_meister/32/15202_2.png) [@wolf\_meister](https://boards.straightdope.com/u/wolf_meister)\
**Post date:** [June 6, 2009, 5:58pm UTC](https://boards.straightdope.com/t/computing-the-dow-jones-industrial-average-for-06-05-2009/498913/3 "2009-06-06T17:58:27Z")

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:smack: Yes **Sunspace** you are right.  
I should have said .005 dollars. :smack:  
(With all those numbers, a mistake had to sneak in someplace).

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**Author:** ![ParentalAdvisory](https://avatars.discourse-cdn.com/v4/letter/p/53a042/32.png) [@ParentalAdvisory](https://boards.straightdope.com/u/ParentalAdvisory)\
**Post date:** [June 6, 2009, 6:02pm UTC](https://boards.straightdope.com/t/computing-the-dow-jones-industrial-average-for-06-05-2009/498913/4 "2009-06-06T18:02:40Z")

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> [@Sunspace](#):
>
> How are the stock values reported? To what fraction of a cent?0.005 cents? Don’t you mean 0.005 _dollars?_

Hehe, reminds me of [http://www.youtube.com/watch?v=lCJ3Oz5JVKs](http://www.youtube.com/watch?v=lCJ3Oz5JVKs)

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**Author:** ![Rigamarole](https://avatars.discourse-cdn.com/v4/letter/r/77aa72/32.png) [@Rigamarole](https://boards.straightdope.com/u/Rigamarole)\
**Post date:** [June 6, 2009, 7:27pm UTC](https://boards.straightdope.com/t/computing-the-dow-jones-industrial-average-for-06-05-2009/498913/5 "2009-06-06T19:27:09Z")

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Wherever you are pulling the stock prices from, somewhere that half of a cent probably got rounded up.

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**Author:** ![wolf\_meister](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolf_meister/32/15202_2.png) [@wolf\_meister](https://boards.straightdope.com/u/wolf_meister)\
**Post date:** [June 7, 2009, 1:54am UTC](https://boards.straightdope.com/t/computing-the-dow-jones-industrial-average-for-06-05-2009/498913/6 "2009-06-07T01:54:29Z")

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**Rigamarole**  
Yep, that’s it. I figured that General Motors was selling at the lowest stock price and would be the most likely candidate.  
I was using GM’s closing price at .87 but the _exact_ closing price is .865 which results in the Dow 30 stock total as 1,100.235 and  
**1,100.235 ÷ 0.125552709 = 8,763.13**  
which is the precise Dow closing figure for June 5, 2009. Thanks for the help folks.

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**Author:** ![SmackFu](https://avatars.discourse-cdn.com/v4/letter/s/53a042/32.png) [@SmackFu](https://boards.straightdope.com/u/SmackFu)\
**Post date:** [June 7, 2009, 10:40pm UTC](https://boards.straightdope.com/t/computing-the-dow-jones-industrial-average-for-06-05-2009/498913/7 "2009-06-07T22:40:23Z")

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We’ve come a long way from when stocks were priced in eights of a dollar.

And that was only in 2001.
