Interestingly, Idaho was ranked 44th in spam volume last year, so its increase in spam rates was dramatic. The U.S. territory of Puerto Rico has the lowest spam volume -- 83.1 percent.
All of the top 10 most spammed states are above the global average. A close second to Idaho is Kentucky (93 percent), followed by New Jersey (92.8 percent), Alabama (91.9 percent), Illinois (91.6 percent), Indiana (91 percent), Massachusetts (90.9 percent), Pennsylvania (90.5 percent), Arizona (90.4 percent), and Maryland (90.3 percent).
"Some of the high spam levels seen across the U.S. can be attributed to the economic challenges experienced globally since the end of 2008, as well as Internet advancement including the high adoption of social networking," said Paul Wood, senior analyst for Symantec's MessageLabs Intelligence. "Spammers have taken full advantage of both the economic uncertainty of some and the trustworthiness of others for their own rewards. Automated tools, resilient botnets, and targeted spam campaigns are all part of the spammers' toolkit, and they are constantly evolving these techniques to outsmart any effort to stop them. No state is immune to the affects of spam."
Less-spammed states include Montana, Alaska, Kansas, South Dakota, Tennessee, Vermont, Rhode Island, Wisconsin, and Florida, according to the MessageLabs report.
MessageLabs says there are between 4 and 6 million bots worldwide responsible for the bulk of spam, and these botnets send more than 87 percent of all unsolicited email, which is around 151 billion email messages per day.
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