NEW YORK -- Stocks that moved heavily or traded substantially on Monday:
Quest Diagnostics Inc., down $2.18 to $109.84.
Medical diagnostics companies held up better than the broader market as the virus outbreak increases the need for testing services.
Marathon Oil Corp., down $3.20 to $3.63.
The price of oil plunged as major crude-producing nations clashed over production plans.
Wells Fargo & Co., down $4.61 to $32.48.
The troubled bank said the chairwoman of its board of directors has resigned.
Royal Caribbean Cruises Ltd., down $16.74 to $48.27.
The U.S. urged citizens to avoid cruise ships because of the increased risk of infection.
Cabot Oil & Gas Corp., up 52 cents to $16.89.
The natural gas producer gained as gas prices fared better than crude oil prices.
Clorox Co., up $1.64 to $174.90.
Sales of disinfectants have surged as the virus outbreak spreads.
Thor Industries Inc., down $18.77 to $51.27.
The company's fiscal second-quarter profit fell short of Wall Street forecasts.
Mylan N.V., down $1.02 to $14.38.
The company's own version of the cancer drug Avastin is being reviewed by U.S. regulators.