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Although most researchers have noted a young skew to the blog audience, a BIGresearch study found that the average age of adult bloggers is actually 37.6. (see chart on left)
A Deloitte & Touche study of blog usage by age found a direct relationship: the younger the user, the more likely he or she was to read or keep a blog on a weekly basis. For example, 55% of millennials (ages 13 to 24) surveyed read a blog, and the percentages declined for every age cohort in the study until reaching just 16% for matures (ages 61 to 75).
Similarly, 35% of millennials kept a blog, whereas only 1% of matures did. The age groups in between—Generation X (ages 25 to 41) and baby boomers (ages 42 to 60)—fell between those two extremes.
With regard to the ethnicity of US adult bloggers, BIGresearch found that 69.7% were white, 20% were Hispanic, 12.2% were African-American and 3.7% were Asian. These percentages were essentially in line with the US Census Bureau's most recent estimates of the demographic breakdown of the US population, allowing for differences in methodologies, mixed-race respondents and overlap between Hispanics and individuals of other ethnicities.
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The number of people creating blogs in the US will also grow, reaching 34.7 million people by 2012—16% of the Internet population. By contrast, there were some 22.6 million US bloggers in 2007, a number that correlates to 12% of Internet users.
Buoyed by these massive levels of consumer engagement, US blog advertising will reach $746 million in 2012, up from $283 million in 2007.