BETHESDA, Md., March 12 /PRNewswire/ -- More than 143 million Americans -- or two thirds of all adults 18 years or older -- are concerned that their personal and financial information would not be kept private and secure if they prepared state and federal tax returns on the Internet, according to a new national poll. A poll ten years ago found that 83 percent of Americans had similar concerns. Both surveys were commissioned by Taxsoftware.com, the only Web site that provides both personal and business tax preparation services online, and which developed the first guaranteed secure Internet-based income tax preparation service. In the latest poll: -- 66 percent said they were "very" or "somewhat" concerned about the safety of their information -- Those most likely to be "very concerned" about the privacy and security of their information included individuals with less than a high school education (47 percent), are retired (41 percent), are not employed (44 percent), and have annual household incomes under $25,000 (48 percent) -- Individuals with a post graduate education were most likely to be "not concerned at all" (41 percent) The poll of 1,000 adults was conducted March 2 -- 4, 2007 by Synovate, and has a margin of error of plus or minus four percent. In 1997, a similar Taxsoftware.com poll found that less than 15 percent of adults "had no concerns at all" versus 32 percent in 2007. Taxsoftware.com spokesperson Mickey Macedo said he was surprised by the increased complacency. "Despite recent high profile media reports about identity theft and the tampering or stealing of government and corporate computer files, a greater percentage of Americans apparently think it won't happen to them if they prepare their taxes online. This increased complacency applies to both men and women, all age groups and income categories, and almost all education levels," Macedo said. "People should not assume the best, but the worst. When it comes to protecting the privacy and security of your financial and personal records, it is better to be safe than sorry. You should only deal with online companies or use Web sites that can guarantee the safety of your information," he said. Macedo observed that "what we said ten years ago when we released our first Internet security survey still holds true today: Based on the Internet's proven and continued vulnerability to vandalism, tampering and break-ins, the American people have good reason to be worried and skeptical about cyber- security. Until adequate and fool-proof protective measures are in place, it's doubtful that the Internet will ever be able to achieve its full potential or be completely trusted by those who use it."