<ARTICLE> 5
<LEGEND>
This schedule contains summary financial information extracted from the
financial statements filed as part of the Company's 10Q and is qualified in its
entirety by reference to such financial statements.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          MAR-31-1998
<PERIOD-END>                               SEP-30-1997
<CASH>                                          14,294
<SECURITIES>                                         0
<RECEIVABLES>                                  105,264
<ALLOWANCES>                                       905
<INVENTORY>                                          0
<CURRENT-ASSETS>                               127,804
<PP&E>                                         276,908
<DEPRECIATION>                                 148,595
<TOTAL-ASSETS>                                 274,305
<CURRENT-LIABILITIES>                           81,328
<BONDS>                                         16,000
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                         6,004
<OTHER-SE>                                     154,251
<TOTAL-LIABILITY-AND-EQUITY>                   274,305
<SALES>                                        185,741
<TOTAL-REVENUES>                               185,741
<CGS>                                          146,176
<TOTAL-COSTS>                                  146,176
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                 122
<INCOME-PRETAX>                                 20,636
<INCOME-TAX>                                     7,958
<INCOME-CONTINUING>                             12,678
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    12,678
<EPS-PRIMARY>                                      .54
<EPS-DILUTED>                                      .54