Trammel claimed 30m based on a remembered estimate of rough sales numbers per year, but the only estimate that’s based on objective evidence - serial number analysis - is 12.5m.
https://web.archive.org/web/20160306232450/http://www.pageta...
Here's an interesting discussion link. Merely being on wikipedia doesn't mean its correct that site is a hive of disinfo in general:
https://www.pagetable.com/?p=547
This site even mentions the peculiar 30M figure.
I would tend to believe the linked site's serial number analysis result of exactly 12.5M. The americans did something like that to the germans in WWII, it turns out a remarkably small totally random sample of sequentially assigned serial numbers is enough to very accurately predict the highest number sold. Assuming very random sampling, which is never truly random, of course.
Doesn't change the overall outcome, however, when there's a stat that a small segment of an industry is "about" the size of what's claimed to be the entire industry, something's off in the numbers.
A mere 12.5M sold remains 5% of the entire USA population at that time, and honestly, having been there, almost everyone I knew had a PC clone or some apple product, usually a mac. The number must be larger than 10%. "a computer" was required at college ... ed.gov claims there are 19.4 M college students in the USA right now and google claims 332M people in the USA right now, so about 6% of the population are in college right now, so back in 1990 guess "around" 6% of the population was required to own a computer just to attend higher ed ... the claimed 10% seems like an incredibly low number.
In 1990? No way. I was taking college courses (for HS credit) in 1990, and the first I heard of a requirement to bring your own computer was years after that.
Another thing that skews the numbers is that my household during the 80s had two Color Computers, a C64, and an Amiga 500, but no one else in my social circle had anything more general than a Nintendo or Atari console.
Computer Science courses generally just required a remote dumb terminal, such as a VT100 or ADM 3a. These were available in a few rooms around campus as well.
One person on my course caused a minor stir by bringing a "laptop" to a lecture to take notes in about 1991 - the keyboard was so noisy that they only did it once!
All engineering students had a computer, though.
Funny how many of the ads say "Call us for more information about our offerings!" instead of a "For more info: www....".
1989 is the very beginning of "the Internet might be useful for general purposes by non-scientists." And incidentally, the same year BGP was dreamed up. https://en.m.wikipedia.org/wiki/The_World_(internet_service_...
So most computers were running boxed retail software with extremely limited hard drive data space (if present at all).
Computer control of modems using standardized Hayes(+) command sets over RS-232 serial ports (1981), the Bell breakup (1984) and subsequent competition, and increased modem manufacturer competition breaking price-per-baud standards and increasing affordability (~1988) were required enablers to take it mass market.
It took until the early 90s that you could (a) buy a PC at a reasonable price, (b) buy a modem at a reasonable price (that was guaranteed to work with your PC), (c) dial into an ISP's local number... from anywhere in the US.
Yes, some people lived in NYC, Chicago, SF, etc. and had access to knowledge and BBS infrastructure at local rates earlier than that, but most people didn't.
I know for a fact 30M commodore 64s were sold in the 80s in the USA. Not all commodores, not all home computers, just the classic model C64, 30M units sold. That's in a country that used to only have 250M people, so in theory 12% of Americans as of 1990 had purchased one specific model, the C64, leaving only 3% for all other models combined, which seems very unlikely.
Some of those probably went to schools not homes, although schools were owned by Apple II in those days...
My suspicion is many of those were unused in basements and closets, or the question was phrased weirdly like "have you purchased a computer in the last three years" or "used a home computer in the last month" or they defined "home computer" to be "not an IBM (office) or Apple (school) product" or something like that.