Updated 4/21/09 12:30 p.m.
In a new column, Mark Penn of the Wall Street Journal casts a mildly-interested eye toward the "profession" of blogging. The Journal will undoubtedly froth up the Interweb and collect thousands of inbound links to this column (including this one ... you're welcome, WSJ), but this piece -- coming from a trustworthy source and written in a reasonable tone -- is a disservice because many of the referenced numbers are old.
Penn is taking heat in the column's comments and via Twitter for fuzzy revenue math, but he's only partially to blame. The controversial sentence -- "It takes about 100,000 unique visitors a month to generate an income of $75,000 a year" -- is paraphrased from Technorati's 2008 State of the Blogosphere report, which includes this line:
"Among active bloggers that we surveyed, the average income was $75,000 for those who had 100,000 or more unique visitors per month (some of whom had more than one million visitors each month). The median annual income for this group is significantly lower -- $22,000."
Proper interpretation of referenced material is certainly important, but in this piece I'm challenging the use of old data. Too often, writers covering Web topics insert links to material without proper consideration of the Internet's hyperactive timeline. Recent technological advances (social networks and mobile usage in particular) and the fickle nature of online audiences (e.g. Friendster to MySpace to Facebook to ??), make it hard for me to put faith in pre-2008 data. Unfortunately, a perusal of the links in one sentence in Penn's column turns up primary sources going back as far as 2005.
Here's the sentence I dug into:
The best studies we can find say we are a nation of over 20 million bloggers, with 1.7 million profiting from the work, and 452,000 of those using blogging as their primary source of income. [Links appear in original column -- text and associated code is copied straight from view source.]
To reiterate, the following links represent "the best studies" Penn and co-writer E. Kinney Zalesne could find.
Link 1: "over 20 million bloggers ..."
The WSJ's direct link goes to the landing page for an eMarketer report from May 2008. I have no argument with the report's timeliness, but a $695 price tag prevented me from digging deeper (my "research expenditure" slush fund got capped at $0 in the '09 budget). I did notice that a +20 million figure shows up in the report's free summary table ("... there were some 22.6 million US bloggers in 2007, a number that correlates to 12% of Internet users."). If that's the source of the "20 million bloggers" link, I'm concerned.
Somewhat related rant/sidenote: I imagine the eMarketer report's author put significant work into the analysis, but years of overblown analyst predictions make my stomach churn when I see stuff like this:
By 2012, more than 145 million people -- or 67% of the US Internet population -- will be reading blogs at least once per month.
There's no way to challenge this because it's a prediction. Analysts look forward, not backwards, so there's little chance we'll see a report in 2012 that puts this figure to the test. What we're left with is a shiny press-release nugget that gets rehashed and referenced ad infinitum.
Moving on ...
Link 2: "1.7 million profiting ..."
The direct link goes to a BlogWorld Expo page that aggregates "Important Blogging Statistics" from four sources:
- A 2005 report from the Pew Internet & American Life Project. Pew does good work, but these numbers are from 2005. To put this in context: neither the iPhone nor Twitter existed when this report came out.
- Technorati founder David Sifry's analysis of Technorati's 2007 "State of the Live Web" report.
- A 2007 Advertising Age chart (PDF) that rounds up data from a number of blog reports, including pre-'08 research from Pew, the Continental Research/KNOT'S Research's International Convergence 2007 Report, the Blog Reader Project from BlogAds (likely the '07 project; definitely not from '08 since the Ad Age piece came out in '07), and Technorati's list of the top blogs. Again, the '07 data is suspect because a lot has changed since then.
Also notable: The BlogWorld Expo page calls out a figure ("37% of blog readers began reading blogs in 2005 or 2006") from the Blog Reader Project, which has ties to ad network demographics. The Blog Reader numbers have relevance, but the context of the data gathering and the intent of the project should also inform the reader's judgement.
- A 2005 ClickZ article that draws numbers from Comscore research (pdf) sponsored by Six Apart, the company behind Movable Type and Typepad, and Gawker Media, a prominent blog network that ran on Movable Type in 2005 and now reportedly uses a customized/hacked version of MT. These are 2005 stats.
Important note: the 1.7 million figure cited by Penn and referenced on the BlogWorld Expo page is not linked to anything.

Is this from a BlogWorld study? It's not clear, which means I have no idea where this information comes from and neither do the folks who created hundreds of references to this exact sentence.
Link 3: "primary source of income ..."
The direct link goes to a Nov. 2008 post on MediaBistro's Galleycat blog, which references stats from Technorati's 2008 State of the Blogosphere report. Interpretation issues aside (see above), I don't have a problem with this data's inclusion in the WSJ column.
To sum up:
Circa 2005 reports: 2 confirmed
Circa 2007 reports: 5 confirmed; potentially 6
Circa 2008 reports: 1 confirmed; potentially 2
If we throw out the eMarketer link because of ambiguity, that leaves us with eight data sources. Only one of those eight is from 2008.
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