While Target has been experiencing dwindling footfall for several years, a new report from research firm Kantar Retail suggests that a massive data breach has negatively impacted the U.S. discount retailer. The report found that 33% of U.S. households reported shopping at a Target or SuperTarget store in January, the lowest penetration in three years and a 22% decline from the previous year. The findings are based on Kantar’s monthly ShopperScape survey of 4,000 primary household shoppers in the U.S. In December it was revealed that the accounts of as many as 40 million credit and debit card holders may have been compromised in a data breach at Target’s U.S. stores between late November and mid-December – a period spanning the key “Black Friday” and holiday shopping periods. The security breach led chief information officer Beth Jacob to resign earlier this month. READ: Target's executive's departure puts spotlight on CIOs The Kantar report said that Target failed to achieve a December “bump” similar to those it has enjoyed in previous years, with the impact of the data breach felt most acutely among two key constituencies: Gen-X and low-income shoppers. The report also found that the latter group’s penetration at Target fell by 30% between January 2013 and January 2014. Amy Koo, a senior analyst with Kantar in Boston, said that the aftermath of the data breach has exposed a “fault line” between Target’s devoted customers and the less-engaged customers it is attempting to reach. READ: In U.S. MasterCard, Visa corral retailers to improve card security She said that Target has been aggressively wooing higher-end ($100,000+ household income) customers in recent years, often at the expense of the Gen-X and low-income constituencies who stopped going to its stores when the data breach was made public. “To some extent there a sentiment of ‘Maybe this store isn’t for me’ if you don’t fit in that guest profile,” she said. Koo said that Target could repatriate customers who have drifted away by transforming its predominantly price-focused “Pay Less” initiatives into an “Expect more. Pay less” proposition that she said resonates and generates long-term brand loyalty.