Retailers have been announcing store closing at a rapid pace in recent months, but the rash of retail closures has only just begun, a new study by Cowen says.

Cowen’s report, released Thursday, suggests that the struggling retail environment is not only caused by a shift in consumer spending moving more to online, as 75 percent of consumers still prefer shopping in-store. In addition, the soft demand is caused by an oversupply of brick-and-mortar retail locations in relation to the population. (See also: Retail Sector: Losers Outweigh Winners in Q1.)

Retailers like Macy’s Inc. (M), J.C. Penney Co. (JCP) and Gap Inc. (GPS) are among the companies that need to hasten the pace of their store closing targets to pare down the glut of stores to better match demand, Cowen analyst Oliver Chen said, according to eMarketer. (See also: Macy’s is Closing 68 Stores.)

There is about 23.5 square feet of shopping space for every person in the U.S., much higher than in other countries. In Canada, there is 16.4 square feet of shopping space per capita, and less than 5 square feet per capita in Italy, France, Spain and the U.K. Indeed, the growth of U.S. malls has rapidly outpaced population growth in the past 46 years. From 1970 to 2016, the number of malls has increased fourfold, versus an increase of 1.5 times for the population.

Macy’s has already said it will close about 14 percent of its stores this year, but Chen’s analysis says that number should be closer to 21 percent. J.C. Penney plans to shutter 14 percent of its stores this year, but Chen believes it should pare back its footprint by 26 percent.

Meanwhile, other stores, namely discount chain retailers, could afford to significantly increase their physical presence. For example, TJX Cos. (TJX), parent of T.J. Maxx and Marshall’s, could increase the number of its locations by 50 percent, according to Cowen.

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