It competes mainly with Dollar Tree and Family Dollar, but also with Target and Wal-Mart.

FORBES: Dollar General: Cash-Strapped Americans Mean Strong Profits Ahead

Analysts say competitors like Target and Costco, as well as discount chains like Dollar Tree and Dollar General, could be seeing fewer customers.

FORBES: Save Money, Shop Less At Wal-Mart: Weak Profit Forecast And Holiday Sales

Among the largest underlying components of SPLV, in trading today AutoZone, Inc. ( NYSE: AZO) is up about 0.4%, Dollar Tree, Inc. ( NASD: DLTR) is up about 0.6%, and Target Corp ( NYSE: TGT) is lower by about 0.1%.

FORBES: SPLV, AZO, DLTR, TGT: ETF Inflow Alert