At the end of a big meal, many homeowners are glad to have a dishwasher to save them some time in cleaning up. But a survey by the U.S. Energy Information Administration has found that dishwashers are not only less common than other appliances in American homes, but also less likely to be used.

Out of 118.2 million primary residences included in the analysis, the survey determined that 80.1 million homes—67.8 percent—had a dishwasher. About one in five homeowners, or 15.9 million, said the dishwasher went unused during a typical week.

Homeowners were most likely to say they used a dishwasher two or three times a week, with EIA determining that 25.8 million households—32.2 percent of those with a dishwasher—used the appliance this frequently. Another 15.4 million households (19.2 percent) used it four to six times per week, while 13.6 million households (17 percent) used it once a week. The remaining 11.7 percent of households, or 9.4 million properties, used the dishwasher at least once a day.

Households with lower incomes were more likely to have older dishwashers that went unused. Thirty-seven percent of those earning less than $20,000 a year and 30 percent of those earning $20,000 to $39,900 said they use the appliance less than once a week.

Nearly every U.S. home had a refrigerator, and an increasing share of homes includes a secondary refrigerator as well. Thirty percent of homes have this appliance, doubling the share recorded in 1997.

Secondary refrigerators are often kept in a garage or basement to provide additional food storage space. However, EIA notes that these appliances also tend to be older and less efficient, consuming more than twice the energy of comparable new refrigerators. Some energy efficiency programs offer rebates and other incentives to recycle secondary refrigerators.

Coffee makers were slightly more popular than toasters in American homes. A total of 64.4 percent of households used a coffee maker at least once a week, compared to 62.8 percent that used a toaster. These items were more than twice as popular as the next most common small appliance, the slow cooker; only 28.3 percent of households used this item at least once a week.

Outdoor grills were used by 58.7 percent of homeowners. Propane was nearly twice as popular as charcoal, with 61 percent of summertime grillers preferring gas while 32 percent used charcoal.

A total of 91.5 percent of homes have a stove, and only 3.1 percent don't use the cooktop at least once a week. The oven was used more infrequently, with 16.8 percent of households not using this part of the stove during a typical week.

Microwaves were found in 96.1 percent of homes, with only 1.4 percent going unused during the week. A total of 82.6 percent of homes had a washer, while 80.6 percent had a dryer. These appliances were also likely to see at least some use during the week; only 1.2 percent of households didn't run at least one load of laundry through the washer during a week, while 2.2 percent of households didn't use the dryer at least once a week.

EIA's Residential Energy Consumption Survey periodically looks at the characteristics of home energy and appliances in the United States. The latest data, collected between August 2015 and April 2016, allowed researchers to consider factors such as housing types and household income. The analysis is based on household surveys, data collected from energy suppliers, and statistical models.