In general, J1 nonstudent visa holders are exempt from the substantial presence test for 2 calendar year. There is a rule for J1 nonstudent visas called the 6 year lookback rule. This rule says that if you were exempt for 2 out of the past 6 years, you cannot be exempt again. So in 2016, you were exempt and a nonresident alien. In 2017 you were not exempt since you were already exempt in 2016 and 2011. In 2018 the exemption from 2011 is more than 6 yeas ago,so yo uwere only exempt for one year in 2016 and will be exempt again from the SPT.
