The components of net periodic benefit expense/(income) for our non-contributory qualified defined benefit pension plan (Primary Pension Plan), non-contributory supplemental pension plans and contributory postretirement health and welfare plan were as follows: | | | | | | | | | | | | | | | | | | Three Months Ended | | Nine Months Ended | ($ in millions) | November 1,
2014 | | November 2,
2013 | | November 1,
2014 | | November 2,
2013 | Primary Pension Plan | | | | | | | | Service cost | $ | 15 |
| | $ | 20 |
| | $ | 46 |
| | $ | 59 |
| Interest cost | 53 |
| | 51 |
| | 158 |
| | 153 |
| Expected return on plan assets | (87 | ) | | (85 | ) | | (261 | ) | | (255 | ) | Amortization of actuarial loss/(gain) | 13 |
| | 38 |
| | 38 |
| | 114 |
| Amortization of prior service cost/(credit) | 1 |
| | 1 |
| | 5 |
| | 4 |
| Loss/(gain) on transfer of benefits | 6 |
| | — |
| | 6 |
| | — |
| Net periodic benefit expense/(income) | $ | 1 |
| | $ | 25 |
| | $ | (8 | ) | | $ | 75 |
| | | | | | | | | Supplemental Pension Plans | | | | | | | | Service cost | $ | — |
| | $ | — |
| | $ | — |
| | $ | — |
| Interest cost | 3 |
| | 3 |
| | 7 |
| | 9 |
| Amortization of actuarial loss/(gain) | 3 |
| | 6 |
| | 11 |
| | 18 |
| Amortization of prior service cost/(credit) | — |
| | — |
| | — |
| | — |
| Loss/(gain) on transfer of benefits | (6 | ) | | — |
| | (6 | ) | | — |
| Net periodic benefit expense/(income) | $ | — |
| | $ | 9 |
| | $ | 12 |
| | $ | 27 |
| | | | | | | | | Primary and Supplemental Pension Plans Total | | | | | | | | Service cost | $ | 15 |
| | $ | 20 |
| | $ | 46 |
| | $ | 59 |
| Interest cost | 56 |
| | 54 |
| | 165 |
| | 162 |
| Expected return on plan assets | (87 | ) | | (85 | ) | | (261 | ) | | (255 | ) | Amortization of actuarial loss/(gain) | 16 |
| | 44 |
| | 49 |
| | 132 |
| Amortization of prior service cost/(credit) | 1 |
| | 1 |
| | 5 |
| | 4 |
| Loss/(gain) on transfer of benefits | — |
| | — |
| | — |
| | — |
| Net periodic benefit expense/(income) | $ | 1 |
| | $ | 34 |
| | $ | 4 |
| | $ | 102 |
| | | | | | | | | Postretirement Health and Welfare Plan | | | | | | | | Service cost | $ | — |
| | $ | — |
| | $ | — |
| | $ | — |
| Interest cost | — |
| | 1 |
| | — |
| | 1 |
| Amortization of actuarial loss/(gain) | — |
| | (1 | ) | | — |
| | (1 | ) | Amortization of prior service cost/(credit) | (2 | ) | | (2 | ) | | (6 | ) | | (6 | ) | Net periodic benefit expense/(income) | $ | (2 | ) | | $ | (2 | ) | | $ | (6 | ) | | $ | (6 | ) | | | | | | | | | Retirement Benefit Plans Total | | | | | | | | Service cost | $ | 15 |
| | $ | 20 |
| | $ | 46 |
| | $ | 59 |
| Interest cost | 56 |
| | 55 |
| | 165 |
| | 163 |
| Expected return on plan assets | (87 | ) | | (85 | ) | | (261 | ) | | (255 | ) | Amortization of actuarial loss/(gain) | 16 |
| | 43 |
| | 49 |
| | 131 |
| Amortization of prior service cost/(credit) | (1 | ) | | (1 | ) | | (1 | ) | | (2 | ) | Loss/(gain) on transfer of benefits
| — |
| | — |
| | — |
| | — |
| Net periodic benefit expense/(income) | $ | (1 | ) | | $ | 32 |
| | $ | (2 | ) | | $ | 96 |
|
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