After getting a big boost in August from the government's "cash for clunkers" car program, consumer spending dropped 0.5% in September, the Commerce Department just reported. It's the largest decline in nine months.

In the same release, Commerce said Americans' personal income was nearly unchanged last month.

Keep in mind: While Commerce said yesterday that gross domestic product grew at a 3.5% annual rate in the third quarter, a sign that the recession might be over, other key indicators — such as consumer spending — also have to flashing green for the economy to really be on the mend.

Check Planet Money for more on the economy's ups and downs.