<TABLE> <S> <C>
<PAGE>
<ARTICLE> 5
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> JUN-30-2000
<CASH> 42,203
<SECURITIES> 0
<RECEIVABLES> 61,479
<ALLOWANCES> 2,482
<INVENTORY> 15,569
<CURRENT-ASSETS> 145,965
<PP&E> 730,593
<DEPRECIATION> 277,766
<TOTAL-ASSETS> 644,226
<CURRENT-LIABILITIES> 115,752
<BONDS> 0
0
0
<COMMON> 158
<OTHER-SE> 315,497
<TOTAL-LIABILITY-AND-EQUITY> 644,226
<SALES> 328,072
<TOTAL-REVENUES> 328,072
<CGS> 225,400
<TOTAL-COSTS> 288,653
<OTHER-EXPENSES> 3,169
<LOSS-PROVISION> 0
<INTEREST-EXPENSE> 0
<INCOME-PRETAX> 36,250
<INCOME-TAX> 10,150
<INCOME-CONTINUING> 26,100
<DISCONTINUED> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> 26,100
<EPS-BASIC> $1.68
<EPS-DILUTED> $1.61
</TABLE>