<TABLE>
                                   Exhibit 12a
<CAPTION>
                STATEMENT SETTING FORTH COMPUTATIONS OF RATIOS OF
                            EARNINGS TO FIXED CHARGES
                             (Dollars in Thousands)

                                     12 Months
                                        Ending                      Year Ended December 31,
                                March 31, 1999         1998         1997         1996         1995        1994
--------------------------------------------------------------------------------------------------------------
<S>                                   <C>          <C>          <C>          <C>          <C>          <C>
EARNINGS AVAILABLE FOR
 FIXED CHARGES
  Pre-tax income:
    Income from continuing
      operations per statement
      of income                       $173,365     $169,612     $125,698     $167,351     $128,382     $ 79,312
    Federal income taxes               112,765      107,904       47,725      107,747       91,519       74,816
    Federal income taxes charged
      to other income - net              4,477        1,807       11,876       (1,608)     (12,068)      22,687
    Capitalized interest                (2,442)      (1,782)        (360)        (600)        (660)        (400)
    Undistributed (earnings) or
      losses of less-than-
      fifty-percent-owned
      entities                              --           --         (608)         460        8,325          743
---------------------------------------------------------------------------------------------------------------
Total                                 $288,165     $277,541     $184,331     $273,350     $215,498     $177,158
---------------------------------------------------------------------------------------------------------------

  Fixed charges:
    Interest expense                  $148,894     $146,140     $123,439     $122,635     $131,346     $126,555
    Other interest                       2,442        1,782          360          600          660          400
    Portion of rentals
      representative of the
      interest factor                    3,390        2,878        3,143        4,187        5,150        5,555
---------------------------------------------------------------------------------------------------------------
Total                                 $154,726     $150,800     $126,942     $127,422     $137,156     $132,510
---------------------------------------------------------------------------------------------------------------

  Earnings available for
    combined fixed charges            $442,891     $428,341     $311,273     $400,772     $352,654     $309,668
RATIO OF EARNINGS TO
  FIXED CHARGES                          2.86x        2.84x        2.45x        3.15x        2.57x        2.34x
</TABLE>

<PAGE>
<TABLE>
                                   Exhibit 12b
                STATEMENT SETTING FORTH COMPUTATIONS OF RATIOS OF
        EARNINGS TO COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS
                             (Dollars in Thousands)
<CAPTION>

                                     12 Months
                                        Ending                      Year Ended December 31,
                                March 31, 1999         1998         1997         1996         1995        1994
--------------------------------------------------------------------------------------------------------------
<S>                                   <C>          <C>          <C>          <C>          <C>          <C>

EARNINGS AVAILABLE FOR COMBINED
 FIXED CHARGES AND PREFERRED
 DIVIDEND REQUIREMENTS

  Pretax income:
    Income from continuing
      operations per statement
      of income                       $173,365     $169,612     $125,698     $167,351     $128,382     $ 79,312
    Federal income taxes               112,765      107,904       47,725      107,747       91,519       74,816
    Federal income taxes charged
      to other income - net              4,477        1,807       11,876       (1,608)     (12,068)      22,687
Subtotal                               290,607      279,323      185,299      273,490      207,833      176,815
  Capitalized interest                  (2,442)      (1,782)        (360)        (600)         660)        (400)
  Undistributed (earnings) or
    losses of less-than-fifty-
    percent-owned entities                  --           --         (608)         460        8,325          743
--------------------------------------------------------------------------------------------------------------
Total                                 $288,165     $277,541     $184,331     $273,350     $215,498     $177,158
--------------------------------------------------------------------------------------------------------------
  Fixed charges:
    Interest expense                  $148,894     $146,140     $123,439     $122,635     $131,346     $126,555
    Other interest                       2,442        1,782          360          600          660          400
    Portion of rentals
      representative of the
      interest factor                    3,390        2,878        3,143        4,187        5,150        5,555
--------------------------------------------------------------------------------------------------------------
Total                                 $154,726     $150,800     $126,942     $127,422     $137,156     $132,510
--------------------------------------------------------------------------------------------------------------
Earnings available for
  combined fixed charges
  and preferred dividend
  requirements                        $442,891     $428,341     $311,273     $400,772     $352,654     $309,668

DIVIDEND REQUIREMENT:
  Fixed charges above                 $154,726     $150,800     $126,942     $127,422     $137,156     $132,510
  Preferred dividend
    requirements below                  21,071       21,414       26,250       36,249       36,674       45,441
--------------------------------------------------------------------------------------------------------------
Total                                 $175,797     $172,214     $153,192     $163,671     $173,830     $177,951
--------------------------------------------------------------------------------------------------------------
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
                                     12 Months
                                        Ending                      Year Ended December 31,
                                March 31, 1999         1998         1997         1996         1995        1994
--------------------------------------------------------------------------------------------------------------
<S>                                   <C>          <C>          <C>          <C>          <C>          <C>
RATIO OF EARNINGS TO COMBINED
  FIXED CHARGES AND PREFERRED
  DIVIDEND REQUIREMENTS                   2.52         2.49         2.03         2.45         2.03         1.74

COMPUTATION OF PREFERRED
  DIVIDEND REQUIREMENTS:
  (a) Pre-tax income                  $290,607     $279,323     $185,299     $273,490     $207,833     $176,815
  (b) Income from continuing
        operations                    $173,365     $169,612     $125,698     $167,351     $128,382     $ 79,312
  (c) Ratio of (a) to (b)               1.6763       1.6468       1.4742       1.6342       1.6189       2.2294
  (d) Preferred dividends             $ 12,570     $ 13,003     $ 17,806     $ 22,181     $ 22,654     $ 20,383
  Preferred dividend
    requirements
      [(d) multiplied by (c)]         $ 21,071     $ 21,414     $ 26,250     $ 36,249     $ 36,674     $ 45,441
</TABLE>