On January 1, 2018, ABC's accumulated post-retirement benefit obligation (APBO) was $3339. During 2018 the following relate to ABC's post-retirement medical plan: retiree benefits paid were $342 service cost was $616 assumptions regarding the trend of future health care costs were revised at the end of 2018, causing the actuary to revise the estimate of the APBO by $1 (positive number is increase in APBO and negative number is decrease) actuary's discount rate is 6%. On December 31, 2018 ABC's APBO is: