Imports of Polystyrene in Japan decreased to 541.27 JPY Million in January from 601.28 JPY Million in December of 2016. Imports of Polystyrene in Japan averaged 608.98 JPY Million from 1988 until 2017, reaching an all time high of 1397.10 JPY Million in April of 1991 and a record low of 257.91 JPY Million in February of 1993.