Family DollarAPShoppers peruse aisles in a Family Dollar store.
Wal-Mart's customers are considerably wealthier than shoppers at dollar stores like Family Dollar and Dollar General, according to new data. 
Four in 10 Family Dollar shoppers have a household income of less than $25,000, which is slightly higher than the poverty level for a family of four, a survey from the consulting firm Kantar Retail shows.
By comparison, 27% of Wal-Mart shoppers' households earn less than $25,000.
The chart below shows the full breakdown by income level:
Wal-Mart shoppersKantar Retail
Overall, Wal-Mart customers have an average household income of $53,125, which is in line with the median income for all U.S. households last year.
Shoppers at Family Dollar and Dollar General earn about $8,000 less annually, with average household incomes of $44,972 and $45,640, respectively.
The dollar stores could be attracting lower-income shoppers because they have been offering lower prices than Wal-Mart. A Sterne Agee survey from earlier this year found that Family Dollar shoppers paid 2.7% less on purchases than Wal-Mart shoppers in January 2014, while Dollar General shoppers paid .2% less.