September is National Coupon Month and in honor of a month dedicated to frugality, has released its annual coupon trends report. According to the report, the residents of Houston, Texas are the most frugal in the nation. In fact, consumers in the South are more frugal than consumers in other parts of the country.

Two other Texas cities made the list of the most frugal cities in the nation for 2011 – Dallas (#7) and San Antonio (#10). Other Southern cities in the top ten list include Atlanta, Georgia (#4) and Miami, Florida (#6).

More Americans are taking advantage of coupons today than they were even a few years ago when the recession was in full swing. In 2010, $3.7 billion in coupons were redeemed, up from about $2.5 billion in 2008. Coupon use in general isn’t just expanding, the use of digital coupons is also on the rise. predicts that approximately half of all coupons redeemed in 2011 will be digital.

So what products are popular among these money-wise coupon clippers? Toilet paper. Yes, toilet paper was the most popular coupon in the nation last year. Other household necessities like paper towels, laundry detergent and fabric softener are also popular among coupon users.

The report also features data on who uses coupons. While 78 percent of American consumers used coupons in 2010, 63 percent of these coupon users were female. Coupon users come in all ages but more coupons were redeemed by individuals aged 18-34 (34 percent) than other groups. Surprisingly, 13 percent of teens and 3 percent of shoppers age 12 and under also used coupons last year.

For more information on coupon use in the United States, download the 2011 Coupon Trend Report (PDF).

Related stories on MNN:

Houston residents love their coupons has named Houston, Texas as the nation's most frugal city.