Statistics on U.S. and worldwide Internet usage growth (separate data
for U.S. and worldwide data, if available), year-to-year data from
1990 forward, or earliest available.

Hi Keith!

Below you will find the statistics on U.S. and Worldwide Internet
usage.  Due to copyright restrictions I am providing direct links to
the data.


=========
Worldwide
=========

The table at the following link shows the number of internet users
worldwide for each year from December 1995 to July 2004.

Source: 
Internet World Stats
http://www.internetworldstats.com/emarketing.htm


=============
United States
=============

The table at the following link provides the number of internet users
in the United States for each year from 1995 to April 2002.

ComputerScope Ltd.: NUA Surveys
http://www.nua.ie/surveys/how_many_online/n_america.html


Internet Adoption
A bar chart showing the change in U.S. Internet penetration over time.
Percent of American Adults Online 1994-2004
http://www.pewinternet.org/trends/InternetAdoption.jpg


Additional statistics:

Worldwide Internet Population 2004: 945 million
(Computer Industry Almanac)

Projection for 2005: 1.10 billion
(Computer Industry Almanac)

Projection for 2006: 1.28 billion
(Computer Industry Almanac) 

Projection for 2007: 1.46 billion
(Computer Industry Almanac) 

ClickZ Stats: Trends & Statistics
http://www.clickz.com/stats/big_picture/geographics/article.php/5911_151151


ETC Media Review provides a wealth of detailed statistics
regarding worldwide internet usage patterns & demographics
http://www.etcnewmedia.com/review/default.asp?SectionID=10 


Search criteria:

Internet population United States 1990..2004
Worldwide Internet population 1990..2004

I hope you find this information useful!

Best regards,
Bobbie7

I did not check the links, so perhaps they qualify the data. Users
could include less than one hour per year and one year old children
who have a computer in their home. User could also inculude persons
who have tried the internet once or twice at the library or a friends
home. User could include persons who occasionally use the work
computer for very restricted access to the internet. User includes
persons who use their computer for a very narrow range of purposes
such as downloading MP3 music. It may even include a few people who
get counted as users because their spouce or child uses a computer in
their home. The one that specified adult, likely tries not to include
persons under age 18.
 I (age 72) use my computer on the internet about 10,000 minutes per
month mostly on forums such as www.seattle.buzz.net  My guess is the
number of heavy users like me is increasing in the USA and elsewhere. 
Neil