Consumer confidence plunged in January to its lowest level in more than a year, reflecting higher Social Security taxes that left Americans with less take-home pay.

The Conference Board said Tuesday that its consumer confidence index dropped to 58.6 in January. That's down from 66.7 in December and the lowest since November 2011.

Conference Board economist Lynn Franco said the tax increase was a key reason confidence tumbled and made Americans less optimistic about the next six months.