Thanks for giving it a go, Yosh.
A few years ago, the US Department of Commerce caught on to the fact
that there was, indeed, something called the IT industry, and began
re-working some of its historical and current data to reflect the
status of the industry in the U.S., and to provide data to track
trends. The data are consistent. However, the U.S. switched its
official industrial classifications in 1999 from the old SIC code
system to a newer system called NAICS. Because of the change-over,
comparisions between pre and post 1999 data are difficult. Commerce
crunched the numbers to make the comparisons for a few years, but not
for all of them -- hence the gaps in the data.
The best, most easily usable form of the information is in the 2001
Statistical Abstract of the United States, in the table entitled: No.
1122. Gross Domestic Income in Information Technologies (IT)
Industries: 1992 to 2000. I won't attempt to reproduce it here,
since experience has demonstrated that it would be a garbled mess.
But you can access the table directly (in PDF format) at:
by going to the section "Section 24. Information and Communications"
and clicking on the link that says: 1119-1159. When the document
opens up, scroll down to Table No. 1122. Your table is there, in all
its glorious detail.
The raw material for these data come from a series of Census Bureau
reports called the Service Annual Survey. The most recent reports for
the Information Sector can be found at the Census Bureau site here:
The site also contains links to earlier reports. These data are much
more unwieldy to work with, but I wanted you to be aware of them, in
case you really want to mine the information in detail.
I hope this is what you needed. But if anything I've written here is
not clear, or needs elaboration, don't hesitate to post a Request for
Clarification, and I'll be happy to assist you further.
And don't forget to tell all your friends about GA!
Search strategy: bookmark pages for the Statistical Abstracts site.