Most popular Halloween candy in the USA

• 72% of all candy spending this Halloween will be on chocolate, says trade group
• Americans spent $12.6 billion on chocolate in the 12 months ended Sept. 8
• The top 10 best-selling chocolate brands are owned by either Hershey or Mars

Chocolate is big business, and Halloween is its biggest holiday. According to a recent survey from the National Confectioners Association, 72% of all candy spending this Halloween will be on chocolate. Last year, more than $12.6 billion was spent on chocolate in the United States, 3.8% more than the year before.

According to market research firm Information Resources, in the past 52 months ending Sept. 8, Americans spent $3.9 billion to buy 3.5 billion chocolate bars, bags and boxes under 3.5 ounces, the standard size consumers pick up at a grocery store checkout. Reese's and M&M's each accounted for more than $500 million in sales. Based on IRI's data, 24/7 Wall St. reviewed the 10 chocolate brands with the largest sales during the last year.

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The chocolate industry is extremely concentrated among just a few competitors. Each of the 10 best-selling chocolate brands is owned by either Hershey (HSY) or Mars. In the past year, Hershey made close to half of all standard-sized chocolate sales in dollars, and Mars accounted for nearly 38% of sales. Only two of the 20 most popular products, Nestle's Butterfinger and Crunch, were made by another company.

The two companies that dominate this market, Hershey and Mars, have been moving in different directions. Dollar sales for the top four Mars brands declined in the past year. Its worst-performing top brand was 3 Musketeers, which fell nearly 10% from the year before. By contrast, sales of all of Hershey's top five brands grew over the past year, led by Kit Kat. Sales of that brand rose by more than 22% to over $300 million.

Most top-selling chocolate brands have been long-time consumer favorites. The nation's oldest top-seller, Hershey's brand chocolate, has been available since 1900. Only two of the brands are relatively new — introduced to the U.S. after 1950. Hershey's Cookies 'N' Creme, the most-recent top-selling chocolate, debuted in 1994.

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These brands not only compete for customer dollars at the checkout line, they also sell their products in other forms. Snack sizes — miniature versions of a chocolate candy bar — are especially popular with trick-or-treaters on Halloween. While most of the top standard size brands also rank among the highest for sales of snack-size chocolate, there are some exceptions. M&M's and 3 Musketeers are relatively less popular in snack size than in the standard size.

Based on data from IRI, a Chicago-based market research firm, 24/7 Wall St. reviewed the top 10 selling chocolate brands in the U.S. during the 52 weeks ending Sept. 8. According to IRI's methodology, chocolate candy sizes fall into multiple categories, including: weighing less than 3.5 ounces, weighing more than 3.5 ounces and snack size (which is excluded from the less than 3.5-ounce category). Our ranking is based on sales of candy units weighing less than 3.5 ounces, which includes most standard size American candy bars. Sales listed were based on sales in U.S. multi-outlet and C-stores (supermarkets, drugstores, mass market retailers, gas/C-stores, military commissaries and select club and dollar retail chains.)

This is America's favorite Halloween candy:

1. Reese's
> Sales: $509.85 million
> Unit sales: 407.44 million
> Average price per unit: $1.25
> Introduced: 1928
> Company: Hershey
Reese's regular size (less than 3.5 oz) peanut butter cups jumped by 7.7% to just under $510 million in the past year, outstripping M&M's from its top spot as the best-selling chocolate. As a result, the brand overtook M&M's as the nation's best-selling chocolate candy. Overall, with Reese's and several other major brands sales growing over the past 12 months, the Hershey Co. dominated the market for standard-size chocolate candy, accounting for roughly 49% of customer spending. Halloween marks a major sales opportunity for Reese's as well. The brand leads in sales of snack-sized packages, which are often given out to trick-or-treaters.

2. M&M's
> Sales: $500.82 million
> Unit sales: 435.18 million
> Average price per unit: $1.15
> Introduced: 1941
> Company: Mars
Sales of M&M's only trail sales of top chocolate brand Reese's by a small amount. But the brand lost its position as the best-selling chocolate after sales fell by more than 3% during the 52 weeks ending in early September. In terms of total units sold, M&M's did even worse, with unit sales down 7.5% from the same period the year before. M&M's also may not see the same sales boost other candy makers see during the Halloween season. Although it is the second highest selling regular size candy, it ranks only eighth among brands in snack-sized sales.

3. Snickers
> Sales: $456.91 million
> Unit sales: 412.81 million
> Average price per unit: $1.11
> Introduced: 1930
> Company: Mars
Snickers bar sales fell by more than 7% to just under 413 million units in the most recent 52 weeks available. This mirrored the decline in the under 3.5 oz category Mars faced across all of its brands, for which unit sales fell by 7.7%. Snickers has been around since 1930, and in recent years has made a major advertising push with its celebrity-filled, "You're not you when you're hungry," campaign. The first commercial in the campaign, which aired during the 2010 Super Bowl, featured actress Betty White getting tackled in a backyard football game. It was an instant sensation.

4. Hershey's
> Sales: $324.63 million
> Unit sales: 308.42 million
> Average price per unit: $1.05
> Introduced: 1900
> Company: Hershey
Hershey has been making many of its most famous brands for decades, and it has made Hershey's branded milk chocolate bars since 1900. Although most of the company's brands have been around for quite a while, Hershey is planning to introduce its first new U.S. brand in decades in 2014. Sales of the company's long-standing brands have risen recently, mostly because of advertising pushes. According to IRI, sales of standard-size Hershey's-branded chocolate bars rose by nearly 8% in dollar terms and 7% in unit terms. The brand's dollar sales for snack sizes, popular around Halloween, have also increased by nearly 12%.

5. Kit Kat
> Sales: $306.51 million
> Unit sales: 275.88 million
> Average price per unit: $1.11
> Introduced: 1935
> Company: Hershey
Sales of few chocolate bars grew faster than Kit Kats over the past year. In that time, the number of Kit Kat bars sold rose 17.8%, while dollar sales rose by more than 22%. Recently, Kit Kat launched a co-promotion with Google, which code-named the most recent version of its Android operating system "KitKat." The Kit Kat brand, owned by Nestle, is popular worldwide. The Hershey Company, however, licenses and manufactures the chocolate in the United States.

MORE:For the rest of the top 10 popular Halloween candy list

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