Last month the national mint intensified production of ¥1 coins in anticipation of the consumption tax hike on April 1. The Ministry of Finance wants 26 million of them manufactured by the end of March, and then another 160 million after the start of the new fiscal year. Once the consumption tax goes up from 5 to 8 percent, retailers will need more small change.

With a 5 percent tax, it's relatively easy for stores to limit their use of coins since they can set prices based on multiples of 5. Maybe it's possible to do that with multiples of 8, too, but not right away, and many fear they will not have enough ¥1 coins on hand when the tax hike goes into effect. An employee of the nationwide ¥100 shop CanDo told Asahi Shimbun, "Altough we sometimes receive ¥1 coins in payment from customers, we don't recycle them as change to other customers, but now we're trying to hoard as many as possible."

If the consumption tax increase is an inconvenience to retailers, it's even more of a pain in the neck for the government, since it costs between ¥2 and ¥3 to make a ¥1 coin, which is 100 percent aluminum. It's the first time the mint has produced ¥1 coins on anything approaching this scale in four years. It will also produce an extra 100 million ¥5 coins, just to be safe. The government doesn't want to relive the small change panic that happened in 1989, when the 3 percent consumption tax was first introduced.