Spiritus in Machina

Acxiom is a data-mining company headquartered in Little Rock, AR. It's also really hard to pronounce (I'm guessing, as I've never actually heard someone say the name) and spell (so much so that it is misspelled as "Axciom" by such luminaries as ZDNet and The Huffington Post). I believe Acxiom prefers to be called a targeted marketing and planning company, or something like that. None of that is particularly relevant to this post, however; please review the following from Acxiom's website:

Last time I checked, the US population was slightly north of 315 million persons (US Census Bureau). Which begs the question, what exactly is Acxiom counting?  It occurred to me that perhaps the 500 million included all the people who have died and been born since Acxiom started keeping records in 1969, going by the name Demographics.  Since that time, approximately 96.3 million US souls have departed this mortal coil, based on CDC info and extrapolating for the last two years (US CDC WONDER Database). The current population already includes new births (as well as anyone born prior to 1969 who is still alive today), so we get to 411.3 million potential US consumers. Something is amiss, I think. My theories:

• Acxiom has multiple instances of the same people, so they have a higher raw count than the actual number of people who exist
• They are rounding up—badly
• You know those duplicate songs, pictures and other files you have on your computer? Acxiom has that problem, too
• Pets have been added to the database
• Imaginary friends are included in the database
• Someone forgot to Google "US population 2013," so instead just guessed from memory
• The immediately preceding person's education was subpar, was hampered by excessive use of mind-altering substances, or both
• Spiritus in Machina

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