This is a very interesting question and recent U.S. Census reports
have started to break out the ratios specifically with a column of
data showing the ?number of males per 100 females.?
You may find this American Fact Finder page on the Census Bureau site
helpful for further research, as it breaks data down into more detail
U.S. Census Bureau
?People,? (Aug. 4, 2004)
It?s this table that has the precise data that you?re seeking:
?Age Groups and Sex: 2000?
It tells an astounding story for the turn of the 21st Century:
* overall there are 96.3 males for every 100 females in the U.S.
* the number of males-per-100-females rises until the 15-19 group,
where they stand at 105.7 to 100.
* at 20-24, the ratio drops to 104.4
* at 25-29, it?s down to 102.3
* at 30-34, it?s now 101.3
* at 35-39, it?s 99.4
* it continues dropping steadily, so that it?s 95.9 at ages 50-54
* by retirement age (65) it?s at 85.7
* after age 75, it?s below 70 males per 100 females
* the ratios are dramatically different than those of the first
Census of the century, when this age range (ages 20-40) had between
102 and 111 men for every 100 women.
For historical information, you?ll want another Census Bureau
publication, the Statistical Abstract of the United States. Different
versions have the population numbers for the century. Most recent
abstracts have data back to 1970.
U.S. Census Bureau
?Statistical Abstract of the United States?
Earlier than 1970, you?ll want to use one of the earlier abstracts, or
a superb summary done titled --
?Bicentennial Edition: Historical Statistics of the United States,
Colonial Times to 1970?
I used the ?Population by Age, Sex & Nativity: 1790-1970? table from
the ?Historical Statistics of the U.S.? for data from 1910-1960.
In order to simplify this, I?ve put the raw data and the male-female
ratios into a spreadsheet here for you. You should be able to view it
in your browser, even if you don?t have Excel. If you do have Excel,
download and save a copy ? then you?ll be able to edit the spreadsheet
or make any additions that you?d like.
?20th Century Censuses ? by gender?
Google search strategy:
U.S. Census Bureau population
?statistical abstract? U.S. population