Table:
|  | 2019 | 2018 | 2017 |
| --- | --- | --- | --- |
|  |  | (in thousands) |  |
| Components of Net Periodic Postretirement Benefit |  |  |  |
| Cost (income): |  |  |  |
| Service cost | $41 | $39 | $34 |
| Interest cost | 347 | 196 | 201 |
| Amortization of prior service credit | (191) | (373) | (496) |
| Net actuarial loss | 717 | 25 | 398 |
| Special termination benefits | — | 3,708 | 591 |
| Total net periodic postretirement benefit cost | 914 | 3,595 | 728 |
| Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income: |  |  |  |
| Prior service cost | — | — | — |
| Reversal of amortization items: |  |  |  |
| Prior service credit | 191 | 373 | 496 |
| Total recognized in other comprehensive income | 191 | 373 | 496 |
| Total recognized in net periodic postretirement cost and other comprehensive income | $1,105 | $3,968 | $1,224 |
Paragraphs:
Expense
For the years ended December 31, 2019, 2018, and 2017, Teradyne’s net periodic postretirement benefit cost (income) was comprised of the following:
Question:
For which years was  Teradyne’s net periodic postretirement benefit cost (income) calculated?
Answer: 2019, 2018, 2017