(Bloomberg) -- Indonesian stocks slumped, heading for their biggest monthly decline in more than 11 years, as investors grew jittery over the economic impact of the fast spreading coronavirus on Southeast Asia’s largest economy.

The benchmark Jakarta Composite Index fell as much as 3.4% to 5,348.878, the lowest since February 2017. The gauge is down 10.1% this month, heading for its worst such performance since October 2008.

Foreign investors have net sold almost $300 million of Indonesian shares this week as the nation’s currency and bonds were also routed. While the rupiah is down 2.4% this week, the worst performance November 2013, the yield on benchmark 10-year government bonds has risen more than 25 basis points, according to data compiled by Bloomberg.

(Corrects to say bond yield rose in third paragraph)

To contact the reporter on this story: Rieka Rahadiana in Jakarta at rrahadiana@bloomberg.net

To contact the editors responsible for this story: Lianting Tu at ltu4@bloomberg.net, Thomas Kutty Abraham, Rieka Rahadiana

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