Family Dollar has over 8,000 units.

Year-over-year retail sales remain robust as The Retail Economist-Goldman Sachs Weekly Chain Store Index showed a 3.4 percent gain. Week to week, sales showed a slight gain of 0.1 percent for the period ended Saturday, Jan. 20.

The year-over-year gains were driven by strong sales at dollar stores and grocery chains, noted Michael P. Niemira, chief economist of The Retail Economist LLC. One of the largest dollar store chains, Dollar General, recently announced a new distribution center in Texas to support its rapid growth.

Amid store closings across the retail sector, Dollar General Corp. opened 1,000 units in 2017, which brought its total store base to over 14,000 stores in 44 states. The Gregg County, Tex. distribution center will be the chain’s 17 DC. Construction is set for early this year, and the facility will generate over 400 jobs. The company has over 1,400 stores in Texas alone.

During its most recent quarterly sales call, the company noted that despite the negative impact of “hurricane-related charges” net income rose 7.7 percent to $253 million on a sales gain of 11 percent to $5 billion. Dollar General is on track to post annual sales next month of $23.5 billion, according to S&P Capital IQ. The retailer’s market capitalization is $27.7 billion.

And more store openings are planned. Todd Vasos, Dollar General’s chief executive officer, said during the call last month that for this year, the company has “plans to execute approximately 2,000 real estate projects comprised of 900 new stores, 1,000 store remodels and 100 store relocations.”

The company’s closest competitor in the dollar store space is Dollar Tree Inc., which operates about 14,330 stores in 48 states. It’s on track to post annual sales of $22 billion, according to S&P Capital IQ. Dollar Tree also owns Family Dollar, which it acquired four years ago in a deal valued at $8.5 billion.

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