<ARTICLE> 5
<MULTIPLIER> 1,000,000
       
                                                                                            
<PERIOD-TYPE>                   3-MOS                   6-MOS                   9-MOS                   12-MOS
<FISCAL-YEAR-END>                          DEC-31-1996             DEC-31-1996             DEC-31-1996             DEC-31-1996
<PERIOD-END>                               MAR-31-1997             JUN-30-1997             SEP-30-1997             DEC-31-1996
<CASH>                                              32                      51                      70                      65
<SECURITIES>                                         0                       0                       0                       0
<RECEIVABLES>                                      314                     316                     338                     252
<ALLOWANCES>                                        33                      35                      41                      35
<INVENTORY>                                        232                     234                     216                     206
<CURRENT-ASSETS>                                   608                     626                     650                     565
<PP&E>                                           1,953                   1,987                   1,992                   1,939
<DEPRECIATION>                                     985                   1,019                   1,031                     975
<TOTAL-ASSETS>                                   2,191                   2,228                   2,255                   2,136
<CURRENT-LIABILITIES>                              376                     376                     394                     321
<BONDS>                                            229                     227                     227                     219
<PREFERRED-MANDATORY>                                0                       0                       0                     214
<PREFERRED>                                          0                       0                       0                       0
<COMMON>                                           214                     214                     215                       0
<OTHER-SE>                                         567                     606                     605                     576
<TOTAL-LIABILITY-AND-EQUITY>                     2,191                   2,228                   2,255                   2,136
<SALES>                                            518                   1,096                   1,671                   2,156
<TOTAL-REVENUES>                                   518                   1,096                   1,671                   2,156
<CGS>                                              347                     725                   1,105                   1,460
<TOTAL-COSTS>                                      347                     725                   1,105                   1,460
<OTHER-EXPENSES>                                    97                     198                     317                     387
<LOSS-PROVISION>                                     0                       0                       0                      46
<INTEREST-EXPENSE>                                   6                      14                      21                      23
<INCOME-PRETAX>                                     68                     159                     228                     240
<INCOME-TAX>                                        23                      55                      90                      75
<INCOME-CONTINUING>                                 46                     104                     138                     165
<DISCONTINUED>                                       0                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0                     (9)
<CHANGES>                                            0                       0                       0                       0
<NET-INCOME>                                        46                     104                     138                     156
<EPS-PRIMARY>                                     1.11                    2.56                    3.39                    3.81
<EPS-DILUTED>                                     1.10                    2.53                    3.35                    3.61