Of the people in the U.S. that were born in 1938 how many of them are
still alive today?
Bonus for breakdown by state, or better yet, county.
Further breakdowns also welcome

bayouguy-ga,

Thanks for an interesting query.  Although it may seem a
straightforward type of question to be asking, it actually involves a
bit of manipulation of population data to arrive at the correct
statistics.


For starters, take a look at the latest "Life Table" from the Census Bureau:  


http://www.cdc.gov/nchs/data/nvsr/nvsr54/nvsr54_14.pdf
United States Life Tables,
April 19, 2006
Table 1. Life table for the total population


Where they indicate that the "Number surviving to 67-68" is 80,105


That is, out of 100,000 people born in a one year period 67-68 years
ago (in other words, born right around 1938), 80,105 are still living.

Put another way, 80.105% of those born in 1938 are still alive today.


By the way, the table also shows that the "Expectation of life
remaining" for this age group is another 17.0 years.




The next question is:  How many people, in total, in this age group
are alive today?  For that figure, one needs to dig into the Census
Bureau's detailed files on population and age:



http://www.census.gov/population/projections/nation/detail/p2001_10.a
National Population Projections
II. Detailed Files
Total Population by Age, Sex, Race, Hispanic Origin, and Nativity:



This table is a bit cryptic, but it shows the age breakout of the US
population for different years of total US population.

The table beings with data for the year 2001, and by scrolling down
you can find a row that begins:


2006 68    1,963,201


This tells us that, in 2006, there are 1,963,201 sixty-eight year olds
in the US.  This number represents 80.105% of the total population
born in 1938.


To summarize:


Number of people born in 1938:  1963201/.80105 =  2,450,784

Number still alive in 2001:  80.105% of 2,450,784 = 1,963,201



As you can see, it takes a bit of number-cruching to arrive at the
particular numbers you are looking for.

On a national basis, similar numbers are available broken out by
gender, race and place of birth.  Quite possibly, data are available
on state and county levels as well.

However, it would take a considerable amount of effort to tease out
the relevant data.  If it is important to you, you may want to make
use of the tables provided here to try and generate some of the
break-outs on your own.  Or, you may want to post one or more
follow-up questions here at Google Answers, describing the types of
breakouts you need.

I trust this information fully answers your question.  

However, please don't rate this answer until you have everything you
need.  If you would like any additional information, just post a
Request for Clarification to let me know how I can assist you further,
and I'm at your service.

All the best,

pafalafa-ga


search strategy -- Used bookmarked links for Census Bureau data.

Super Job!  I had looked hours for this information and was unable to
find it.  Many, many thanks.