The historic selloff in Target Corp’s stock TGT, -24.36% is casting a pall on the retail sector, as shares of 90 of the S&P 500’s SPX, -2.85% 92 consumer discretionary and staples companies are trading lower. Target’s stock was the weakest of the bunch, tumbling 24.7% toward an 18-month low, as well as the biggest one-day plunge since Black Monday (Oct. 19, 1987), after a hugely disappointing earnings report. The SPDR Consumer Staples Select Sector ETF XLP, -4.76% slumped 4.7%, with all 32 components losing ground, while the SPDR Consumer Discretionary Select Sector ETF XLY, -5.14%, of which Target is a component, also dropped 4.7% with 58 of 60 components falling. Among some of the more sympathetic losers, shares of fellow discount retailers Dollar Tree Inc. DLTR, -16.15% tumbled 17.2% and Dollar General Corp. DG, -11.40% slid 12.2%, while membership-based warehouse retailer Costco Wholesale Corp COST, -11.45% sank 11.6%. Drug store chain and health care services company Walgreens Boots Alliance Inc.’s stock WBA, -6.75% dropped 6.6%, and was the Dow Jones Industrial Average’s DJIA, -2.43% biggest decliner. Walmart Inc.’s stock WMT, -7.08% slumped 5.9%, after tumbling 11.4% on Tuesday on the back of disappointing earnings. The two retail gainers were shares of discount retailers TJX Companies Inc. TJX, +8.64%, which rallied 9.1% after an earnings beat, and Ross Stores Inc. ROST, +1.25%, which tacked on 2.6%.