A college education may not be worth as much as you think.

For years, higher education was touted as a safe path to professional and financial success. Graduates, it has long been argued, would be able to build solid careers that would earn them far more than their high-school educated counterparts.

The numbers appeared to back it up. In recent years, the nonprofit College Board touted the difference in lifetime earnings of college grads over high-school graduates at $800,000, a widely circulated figure. Other estimates topped $1 million.

But now, as tuition continues to skyrocket and many seeking to change careers are heading back to school, some researchers are questioning the methodology behind the high projections.

Most researchers agree that college graduates, even in rough economies, generally fare better than individuals with only high-school diplomas. But just how much better is where the math gets fuzzy.

The problem stems from the common source of the estimates, a 2002 Census Bureau report titled 'The Big Payoff.' The report said the average high-school graduate earns $25,900 a year, and the average college graduate earns $45,400, based on 1999 data. The difference between the two figures is $19,500; multiply it by 40 years, as the Census Bureau did, the result is $780,000.

'The idea was not to produce a definitive 'This is what you'll earn' number, but to try and give some measure of the relative value of education attainments,' says Eric Newburger, a lead researcher at the Census and the paper's co-author. 'It's not a statement about the future, it's a statement about today.'

Mark Schneider, a vice president of the American Institutes for Research, a nonprofit research organization based in Washington, calls it 'a million-dollar misunderstanding.'

One problem he sees with the estimates: They don't take into account deductions from income taxes or breaks in employment. Nor do they factor in debt, particularly student debt loads, which have ballooned for both public and private colleges in recent years. In addition, the income data used for the Census estimates is from 1999, when total expenses for tuition and fees at the average four-year private college were $15,518 per year. For the 2009-10 school year, that number has risen to $26,273, and it continues to increase at a rate higher than inflation.

Dr. Schneider estimated the actual lifetime-earnings advantage for college graduates is a mere $279,893 in report he wrote last year. He included tuition payments and discounted earning streams, putting them into present value. He also used actual salary data for graduates 10 years after they completed their degrees to measure incomes. Even among graduates of top-tier institutions, the earnings came in well below the million-dollar mark, he says.

'Averages don't tell the whole story,' says Lauren Asher, president of the Institute for College Access & Success, a nonprofit group based in Berkeley, Calif. She points out that incomes vary widely, especially based on majors. 'The truth is that no one can predict for you exactly what you're gong to earn,' she says.

And that includes the College Board, which recently said on its Web site: 'Over a lifetime, the gap in earning potential between a high-school diploma and a bachelor of arts is more than $800,000. In other words, whatever sacrifices you and your child make for [a] college education in the short term are more than repaid in the long term.'

The $800,000 number, it turns out, was pulled from a footnote of the College Board's 2007 'Education Pays' report that explained lifetime earnings. The report's author, Sandy Baum -- an emeritus Skidmore College economics professor who didn't write the promotional text -- says that $450,000 is actually a more reasonable estimate of the difference in lifetime earnings, something she's said in interviews for more than a year.

Steve Talbott, a journalism professor at Cleveland State University, who is researching the cost of education, says he urged the College Board to take down the 'misleading use' of the $800,000 number a year ago.

A College Board spokeswoman says it doesn't have a record of when the content was written and that 'it's possible that during an update of the content the writer misinterpreted the data.' She also says the text represented old data and reflected 'a different methodology.' The $800,000 figure was removed from its Web site in December, once the group learned of the error, she says.

大学教育的价值可能没你想的那么高。

多年来，高等教育被吹嘘为通向事业和经济成就的阳关大道。人们长久以来认为，相比仅受过高中教育者，大学毕业生有能力打下坚实的职业基础，挣的钱也要多得多。

大学毕业生和高中毕业生之间的收入差距并不像此前报导得那么明显。相关数据似乎也佐证了这种观点。近年来，非营利机构College Board声称大学毕业生一生比高中毕业生多挣80万美元，这个数字被广泛引用。其他一些估计超过100万美元。

但如今，在学费继续一路飙升、许多想转换职业的人回到学校之际，一些研究人员却在质疑上述宏伟前景背后的方法论。

大多数研究人员都认为，大学毕业生通常比只有高中文凭者过得好，即便在经济不景气时也是如此。不过好到什么程度则没那么容易算得清楚明白。

问题的根源在于上述预计所使用的同一份资料──2002年美国人口普查局（Census Bureau）的一份名为《巨大的回报》（The Big Payoff）的报告。报告说，高中毕业生平均年薪2.59万美元，大学毕业生平均年薪4.54万美元，其依据的是1999年数据。二者平均年薪的差额为1.95万美元，再乘以40年（人口普查局就是这么干的）,结果就是78万美元。

人口普查局的研究员、该报告作者之一纽伯格（Eric Newburger）说，报告并不是要给出一个"你赚的就是这么多"的数字，而是试图衡量教育背景的相对价值。它并不是对未来情况的表述，只是表明当前的情况。

华盛顿的非营利研究机构美国研究协会（American Institutes for Research）副主席施耐德（Mark Schneider）说，这是个价值百万的误解。

他觉得上述估计数字的一个问题是，它们没有减掉所得税或算上中断就业的情况。另外它们也没有计入债务，尤其是学生贷款，近年来公立和私立大学的这类贷款都不断膨胀。除此之外，人口普查局报告使用的收入数据是1999年的，当时四年私立大学的学杂费总计为每年15,518美元。2009-10学年，这一数字已经增加到26,273美元，而且还在以高于通胀的速度继续上涨。

施耐德在去年撰写的一份报告中估计，大学毕业生一生中多挣的钱仅为279,893美元。他将学费和未来收入折现的情况都包括进来，使之以当前价值来体现。他还使用了毕业生完成学业10年后的实际薪水数据来衡量收入。他说，即便是最好学府的毕业生，其平均收入也远远不到100万美元。

加州非营利组织Institute for College Access & Success的主席阿什尔（Lauren Asher）说，平均数不能说明整体情况。她指出，薪水差距很大，尤其是不同专业。她说，说真的，没人能精确预测你到底能赚多少钱。

College Board也无法准确预测。该机构不久前在其网站上说，持高中文凭者和文科学士一生收入的差距超过80万美元。换句话说，无论你和你的孩子在短期内为上大学而做出何种牺牲，从长远看都是超值的。

结果发现，80万美元这个数字是来自College Board在2007年的《教育回报》（Education Pays）报告中的一个脚注，该报告解释了终生收入。报告作者、斯克德摩尔学院（Skidmore College）荣誉经济学教授鲍姆（Sandy Baum）说，45万美元是上述两个人群终生收入差距的更合理估计，她一年多以前接受采访时就提出过这一点。上述宣传文字并不是出自鲍姆之手。

克利夫兰州立大学（Cleveland State University）新闻学教授塔波特（Steve Talbott）在进行教育成本方面的研究，他说他敦促College Board撤销一年前对80万美元这个数字的误用。

College Board发言人说，该机构没有记录这一内容的写作时间，有可能作者是在更新时对数据产生了曲解。她还表示，上述文字反映的是以前的数据和"不同的方法论";该机构知悉这一错误后，已经于去年12月将80万美元的数字从网站上拿掉。