BUENOS AIRES, Jan 18 (Reuters) - Argentine stocks slipped on Friday for a fourth straight session, pressured by persistent worries about fallout from a U.S. economic downturn and the absence of institutional investors, traders said.
The MerVal index .MERV of 42 leading companies closed 0.43 percent lower at 2,002.46 points, pushing losses to more than 6 percent since Monday.
"The MerVal fell again in line with Wall Street's erratic behavior amid fears about the (U.S.) economy," said Horacio Corneille, trader at a company that bears his name.
Volume on the broad market was a weakish 88 million pesos ($28 million); 29 active shares advanced, 46 declined and 10 were unchanged.
"Institutional investors have been missing for days and this affects the MerVal's volatility, creating a cautious and lateral market," said Francisco Marra, an analyst at Bull Market Brokers.
The MerVal's losses were led by natural gas distributor Metrogas (MET.BA), which sank 8.6 percent to 1.17 pesos a share.
Sovereign bonds traded locally fell for a fourth straight day, ending 1.4 percent lower on average.
The worst losses were seen in Par bonds denominated in pesos, which fell 1.6 percent.
The peso ended steady. In informal trade between foreign exchange houses, as measured by Reuters, the currency ended flat at 3.1775/3.1800 per dollar ARSB=.
In formal interbank trade, the peso slipped 0.08 percent to close at 3.1500/3.1525 ARS=RASL. (Reporting by Walter Bianchi; Writing by Hilary Burke; Editing by Jonathan Oatis)