Shares plunged on the Taiwan Stock Exchange in Taipei early today, driven by fears that last week's killer earthquake would rock the economy and take a toll on corporate profits. Blue chips tumbled 2.7% in the first few minutes of trading. The government had sought to contain panic selling, announcing temporary measures late Sunday placing emergency limits on how far shares can fall in a single session during the next two weeks. Finance Minister Paul Chiu said shares would be allowed to fall no more than 3.5% a day--half the usual daily limit--to "ensure that market order can be sustained." The market had been closed since Tuesday, when a 7.6-magnitude earthquake killed more than 2,000 people and damaged the island's export-based economy. Analysts predict that Taiwan's 1999 economic growth will fall to around 5.5%, versus forecasts of 5.7%.