<TABLE>
                                                                                                  Exhibit 12a
                STATEMENT SETTING FORTH COMPUTATIONS OF RATIOS OF
                            EARNINGS TO FIXED CHARGES
                             (Dollars in Thousands)
<CAPTION>
                                   12 Months
                                   Ending                       Year Ended December 31,
                                   September
                                   30,  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                    $ 187,825    $ 169,612    $ 125,698    $ 167,351    $ 128,382    $  79,312
    Federal income taxes             111,220      107,904       47,725      107,747       91,519       74,816
    Federal income taxes charged
      to other income - net            6,903        1,807       11,876       (1,608)     (12,068)      22,687
    Capitalized interest              (4,677)      (1,782)        (360)        (600)        (660)        (400)
    Undistributed (earnings) or
      losses of less-than-
      fifty-percent-owned
      entities                            --           --         (608)         460        8,325          743
--------------------------------   ---------    ---------    ---------    ---------    ---------    ---------
Total                              $ 301,271    $ 277,541    $ 184,331    $ 273,350    $ 215,498    $ 177,158
--------------------------------   ---------    ---------    ---------    ---------    ---------    ---------

  Fixed charges:
    Interest expense               $ 155,108    $ 146,140    $ 123,439    $ 122,635    $ 131,346    $ 126,555
    Other interest                     4,677        1,782          360          600          660          400
    Portion of rentals
      representative of the
      interest factor                  4,214        2,878        3,143        4,187        5,150        5,555
--------------------------------   ---------    ---------    ---------    ---------    ---------    ---------
Total                              $ 163,999    $ 150,800    $ 126,942    $ 127,422    $ 137,156    $ 132,510
--------------------------------   ---------    ---------    ---------    ---------    ---------    ---------

  Earnings available for
    combined fixed charges         $ 465,270    $ 428,341    $ 311,273    $ 400,772    $ 352,654    $ 309,668
RATIO OF EARNINGS TO
  FIXED CHARGES                        2.84x        2.84x        2.45x        3.15x        2.57x        2.34x

</TABLE>

                                       1
<PAGE>
<TABLE>
                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,
                                   September
                                   30, 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                    $ 187,825    $ 169,612    $ 125,698    $ 167,351    $ 128,382    $  79,312
    Federal income taxes             111,220      107,904       47,725      107,747       91,519       74,816
    Federal income taxes charged
      to other income - net            6,903        1,807       11,876       (1,608)     (12,068)      22,687
Subtotal                             305,948      279,323      185,299      273,490      207,833      176,815
  Capitalized interest                (4,677)      (1,782)        (360)        (600)        (660)        (400)
  Undistributed (earnings) or
    losses of less-than-fifty-
    percent-owned entities                --           --         (608)         460        8,325          743
--------------------------------------------    ---------    ---------    ---------    ---------    ---------
Total                              $ 301,271    $ 277,541    $ 184,331    $ 273,350    $ 215,498    $ 177,158
--------------------------------------------    ---------    ---------    ---------    ---------    ---------

  Fixed charges:
    Interest expense               $ 155,108    $ 146,140    $ 123,439    $ 122,635    $ 131,346    $ 126,555
    Other interest                     4,677        1,782          360          600          660          400
    Portion of rentals
      representative of the
      interest factor                  4,214        2,878        3,143        4,187        5,150        5,555
--------------------------------------------    ---------    ---------    ---------    ---------    ---------
Total                              $ 163,999    $ 150,800    $ 126,942    $ 127,422    $ 137,156    $ 132,510
--------------------------------------------    ---------    ---------    ---------    ---------    ---------

Earnings available for
  combined fixed charges
  and preferred dividend
  requirements                     $ 465,270    $ 428,341    $ 311,273    $ 400,772    $ 352,654    $ 309,668

DIVIDEND REQUIREMENT:
  Fixed charges above              $ 163,999    $ 150,800    $ 126,942    $ 127,422    $ 137,156    $ 132,510
  Preferred dividend
    requirements below                19,395       21,414       26,250       36,249       36,674       45,441
--------------------------------------------    ---------    ---------    ---------    ---------    ---------
Total                              $ 183,394    $ 172,214    $ 153,192    $ 163,671    $ 173,830    $ 177,951
--------------------------------------------    ---------    ---------    ---------    ---------    ---------
</TABLE>
                                       2
<PAGE>
<TABLE>
<CAPTION>
                                   12 Months
                                   Ending                     Year Ended December 31,
                                   September
                                    30, 1999        1998         1997         1996         1995         1994
--------------------------------   ---------    ---------    ---------    ---------    ---------    ---------
<S>                                <C>          <C>          <C>          <C>          <C>          <C>
RATIO OF EARNINGS TO COMBINED
  FIXED CHARGES AND PREFERRED
  DIVIDEND REQUIREMENTS                 2.54         2.49         2.03         2.45         2.03         1.74

COMPUTATION OF PREFERRED
  DIVIDEND REQUIREMENTS:
  (a) Pre-tax income                $305,948    $ 279,323    $ 185,299    $ 273,490    $ 207,833    $ 176,815
  (b) Income from continuing
        operations                  $187,825    $ 169,612    $ 125,698    $ 167,351    $ 128,382    $  79,312
  (c) Ratio of (a) to (b)             1.6289       1.6468       1.4742       1.6342       1.6189       2.2294
  (d) Preferred dividends           $ 11,907    $  13,003    $  17,806    $  22,181    $  22,654    $  20,383
  Preferred dividend
    requirements
      [(d) multiplied by (c)]       $ 19,395    $  21,414    $  26,250    $  36,249    $  36,674    $  45,441
</TABLE>
                                       3
<PAGE>