<ARTICLE>                    5
<MULTIPLIER>                 1000
<CURRENCY>                   U.S. DOLLARS
       
                          
<PERIOD-TYPE>                9-MOS
<FISCAL-YEAR-END>                                                       MAR-31-1998
<PERIOD-START>                                                          APR-01-1997
<PERIOD-END>                                                            DEC-31-1997
<EXCHANGE-RATE>                                                                   1
<CASH>                                                                       41,844
<SECURITIES>                                                                      0
<RECEIVABLES>                                                                62,053
<ALLOWANCES>                                                                      0
<INVENTORY>                                                                  58,742
<CURRENT-ASSETS>                                                            195,744
<PP&E>                                                                      318,363
<DEPRECIATION>                                                                    0
<TOTAL-ASSETS>                                                              518,514
<CURRENT-LIABILITIES>                                                       140,484
<BONDS>                                                                       2,410
<PREFERRED-MANDATORY>                                                             0
<PREFERRED>                                                                       0
<COMMON>                                                                         54
<OTHER-SE>                                                                  368,494
<TOTAL-LIABILITY-AND-EQUITY>                                                518,514
<SALES>                                                                     303,814
<TOTAL-REVENUES>                                                            303,814
<CGS>                                                                       152,476
<TOTAL-COSTS>                                                               152,476
<OTHER-EXPENSES>                                                             33,599
<LOSS-PROVISION>                                                                456
<INTEREST-EXPENSE>                                                              835
<INCOME-PRETAX>                                                              68,686
<INCOME-TAX>                                                                 18,545
<INCOME-CONTINUING>                                                          50,141
<DISCONTINUED>                                                                    0
<EXTRAORDINARY>                                                                   0
<CHANGES>                                                                         0
<NET-INCOME>                                                                 50,141
<EPS-PRIMARY>                                                                  0.94
<EPS-DILUTED>                                                                  0.89