NEW YORK — Americans are feeling worse about the economy than they have in a long time — a fact that could have wide-reaching implications from Walmart to the White House.

Despite improving job and housing markets, consumer confidence fell to the lowest level since November 2011, according to the Conference Board, a private research group. The index has been on a roller coaster ride this year. It declined in January, rose in February, and then posted four months of declines before registering an increase in July.

August’s reading indicates the gains in the job and housing markets aren’t big enough to put to rest Americans’ economic fears. That not only threatens to put a damper on retail sales for the back-to-school and winter holiday seasons — the two biggest shopping periods of the year — but it could also affect how Americans vote in November’s presidential election.

Mark Vitner, a Wells Fargo Securities senior economist, said he has looked at October confidence figures since 1972. No president has been reelected when confidence was below 90, which indicates a healthy economy. The index has not reached that high since December 2007.

The Conference Board said its Consumer Confidence Index in August fell to 60.6, down from a revised 65.4 in July and the 66 analysts were expecting. The index now stands at the lowest since November 2011, when the reading was at 55.2.

‘‘This report is a little disturbing going into the fall,’’ Vitner said. ‘‘Consumers are less optimistic about the future.’’

The August confidence reading shows that despite signs the economy is recovering, many Americans aren’t encouraged by the snail’s pace.

Home prices rose 0.5 percent in June from the same month last year, the first year-over-year increase since summer 2010, according to the Standard & Poor’s/Case-Shiller home price index. All 20 cities tracked by the index rose in June from May, the second consecutive time every city posted month-over-month gains.

Employers added 163,000 jobs in July, the most since February. The gains averaged 73,000 jobs a month from April through June, but that’s not enough to keep up with a rising population, and the US unemployment rate increased to 8.3 percent, from 8.2 percent in June.

The economy grew at an annual rate of 1.5 percent April through June, down from 2 percent in the first quarter and 4.1 percent in the fourth quarter of 2011.

‘‘Consumers were more apprehensive about business and employment prospects,’’ Lynn Franco, director of economic indicators at the Conference Board, said in a statement.

The Consumer Confidence index, based on a survey Aug. 1 to 16 of 500 randomly selected people nationwide, underscored the anxiety about the future. Consumer confidence is widely watched because consumer spending accounts for about 70 percent of US economic activity.

In the latest reading, the percentage of consumers expecting business conditions to improve over the next six months declined to 16.5 percent from 19. Those expecting more jobs declined to 15.4 percent from 17.6 percent, while those expecting fewer jobs rose to 23.4 percent from 20.6 percent.

Americans’ outlook may also be influenced by gas prices. They fell sharply from a peak of $3.94 in early April but have started to surge again in recent weeks. Gas prices at the pump rose 19 cents to $3.71, on average, during the survey period.

Americans also worry the economy will go off a ‘‘fiscal cliff’’ at the end of the year, said Vitner, the Wells Fargo economist. That’s when tax increases and deep spending cuts will take effect, unless Congress reaches a budget agreement by then.

Americans who have jobs appear to be optimistic about one thing: their future earnings potential. According to the index, the proportion of consumers expecting an increase in their incomes improved to 15.7 percent from 14.2 percent.

Jason Wilczak, 29, of Broad Brook, Conn., said he is feeling better this month after he learned of a $10,000 pay raise. Wilczak, who has two children, had been a machinist but retrained as a software developer. He will now make $65,000 a year.

‘‘As far as I’m concerned,” he said, “things are moving in the right direction.’’