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