eMarketer reports that pharmaceutical companies are the biggest spam culprits, above porn and gambling properties.

Pharmaceutical messages are among the most pervasive spam consumers receive. A recent "Spam Personality" survey by Reflexion Network Solutions showed that 97.4 percent of respondents said they received spam advertising medications, slightly more than shopping, body enhancements, pornography and gambling spam. The survey showed that people receive between 50 and 200 emails every day, and 20 percent of the 157 respondents said that one-half to three-quarters of their incoming email was spam. Given that some respondents had an average of 3.2 active email addresses, that's a lot of spam to delete.

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