nhk world's reiko sakurai sat down with sims to hear his views and their implications for abenomics. >> reporter: christopher sims thinks that japan's aggressive monetary easing isn't working and won't work as it is. it's a year since the bank of japan has introduced a negative interest policy, but it's hard from hitting the inflation target. what went wrong? >> i was very optimistic about abenomics at the beginning, but then when the consumption tax increase was implemented in the midst of this, i realized there really was no coordination of fiscal and monetary policy, and the public realized it, too, that there was going to be contractionary fiscal policy working against the expansionary monetary policy, and i think that's why it's had little effect until recently. so, in order for it to have a truly expansionary effect, the fiscal policy has to also be aimed at getting inflation back up to the target level. >> reporter: sims says prime minister shinzo e should announce he'llll postpone the consumption tax hike planned for 2019 until the bank of japan hits its 2% inflation target.