The study looked at how prices are set in Japan using data from 1989 to 2003. They found that prices for goods change often, but prices for services change less. Prices for goods increased in the 1990s, while prices for services decreased. Many items have prices that go down over time. The drop in inflation since the 1990s is mostly due to fewer price changes, not the size of the changes. The differences in how often prices change are influenced by labor costs and how firms decide on sales.