<ARTICLE> 5  
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          APR-30-1998
<PERIOD-START>                             MAY-01-1997
<PERIOD-END>                               OCT-31-1997
<CASH>                                          14,367
<SECURITIES>                                    14,265
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<ALLOWANCES>                                       377
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<PP&E>                                          38,162
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<CURRENT-LIABILITIES>                            8,732
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<CGS>                                           23,150
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<EPS-PRIMARY>                                      .27
<EPS-DILUTED>                                      .27
<FN>
<F1>RESEARCH & DEVELOPMENT
<F2>PROVISION FOR BAD DEBT
</FN>