|                                                                     |   | 3 Months      Ended |   |   | 12 Months      Ended |    |    | 12 Months      Ended          |   |
|--------------------------------------------------------------------------|--------|---------------------|--------|--------|----------------------|---------|---------|-------------------------------|--------|
|                                                                     |   | Mar.      31,       |   |   | Mar.      31,        |    |    | Dec.      31,                 |   |   | Dec.      31, |   |   | Dec.      31, |   |   | Dec.      31, |   |   | Dec.      31, |   |
|                                                                     |   | 2008                |   |   | 2008                 |    |    | 2007                          |   |   | 2006 |   |   | 2005 |   |   | 2004 |   |   | 2003 |   |
|                                                                     |   |                |   |   |                 |    |    | - Thousands      of Dollars - |   |
| Fixed      Charges:                                                      |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Interest      on Long-Term Debt                              |   | $                   | 11,712 |   |                 | $       | 49,504  |                          |   | $ | 50,230 |   |   | $ | 51,422 |   |   | $ | 56,243 |   |   | $ | 69,904 |   |   | $ | 76,585 |   |
|   Other      Interest (1)                                      |   |                | 1,005  |   |                 |    | 3,984   |                          |   |   | 4,538 |   |   |   | 6,436 |   |   |   | 2,597 |   |   |   | 1,263 |   |   |   | 1,820 |   |
|   Interest      on Capital Lease Obligations                   |   |                | 14,329 |   |                 |    | 62,660  |                          |   |   | 64,477 |   |   |   | 72,556 |   |   |   | 79,064 |   |   |   | 85,869 |   |   |   | 84,053 |   |
| Total      Fixed Charges                                                 |   | $                   | 27,046 |   |                 | $  | 116,148 |                          |   | $  | 119,245 |   |   | $  | 130,414 |   |   | $ | 137,904 |   |   | $ | 157,036 |   |   | $ | 162,458 |   |
|                                                                     |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Net      Income                                                          |   |                | (8,862 | )      |                 |    | 43,773  |                          |   |   | 53,456 |   |   |   | 66,745 |   |   |   | 48,267 |   |   |   | 46,127 |   |   |   | 128,913 |   |
|                                                                     |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Less:                                                                    |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   Cumulative      Effect of Accounting Change -                |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|       Net      of Tax                      |   |                | -      |   |                 |    | -       |                          |   |   | - |   |   |   | - |   |   |   | (626 | ) |   |   | - |   |   |   | 67,471 |   |
| Net      Income/(Loss) from Continuing Operations                        |   |                | (8,862 | )      |                 |    | 43,773  |                          |   |   | 53,456 |   |   |   | 66,745 |   |   |   | 48,893 |   |   |   | 46,127 |   |   |   | 61,442 |   |
|                                                                     |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Add      (Deduct):                                                       |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   (Income)      Losses from Equity  Investees    (2) |   |                | (1,381 | )      |                 |    | (1,381  | )                             |   |   | - |   |   |   | (320 | ) |   |   | (314 | ) |   |   | (131 | ) |   |   | (76 | ) |
|   Income      Taxes                                            |   |                | 4,336  |   |                 |    | 30,138  |                          |   |   | 35,542 |   |   |   | 42,478 |   |   |   | 33,907 |   |   |   | 34,815 |   |   |   | 21,090 |   |
|   Total      Fixed Charges                                     |   |                | 27,046 |   |                 |    | 116,148 |                          |   |   | 119,245 |   |   |   | 130,414 |   |   |   | 137,904 |   |   |   | 157,036 |   |   |   | 162,458 |   |
|                                                                     |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Total      Earnings before Taxes and Fixed      Charges                  |   | $                   | 21,139 |   |                 | $       | 188,678 |                          |   | $ | 208,243 |   |   | $ | 239,317 |   |   | $ | 220,390 |   |   | $ | 237,847 |   |   | $ | 244,914 |   |
|                                                                     |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                     |   |                |   |   |                 |    |    |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Ratio      of Earnings to Fixed Charges                                  |   |                | 0.782  |   |                 |    | 1.624   |                          |   |   | 1.746 |   |   |   | 1.835 |   |   |   | 1.598 |   |   |   | 1.515 |   |   |   | 1.508 |   |