The nation's $16 trillion-plus debt has some Americans so worried that they've donated nearly $8 million to help pay it off.

Yes, it's less than a drop in the bucket, but every little bit helps, according to the Bureau of the Public Debt, which accepts such "gifts." The donations have been going up since the 2008 federal fiscal year, when Americans donated $2.1 million. Last year, $3.2 million was donated.

This year, donations jumped to $7.7 million.

According to a CNN report, the first contribution to the national debt was in 1961 when an anonymous estate left Uncle Sam $20 million. A law was passed to accept the money and donations have trickled in ever since. The bureau says $85 million has been donated so far.

And just in case you're in a giving mood, Uncle Sam wants you to know you can make checks payable to the Bureau of the Public Debt and please note that it's "a Gift to reduce the Debt Held by the Public."

There's a counter-productive irony to this: The gift is tax-deductible, which lowers your tax payment, a loss of income to the country that could, in turn, contribute to raising the debt.

To take a peek at the public debt, visit the website: www.treasurydirect.gov.