If we control for , which takes into account deflation and reflects the average well-being of the Japanese people, in the per capita GDP calculations, Japanese growth simply wavered during the 1990s.

Purchase price parity.

Explanation:

Purchase prices parity is a tool that is used to compare the purchasing power of two currencies by using a certain good. It consider purchasing power of different locations.

Purchase price parity is calculated by dividing price of one basket of goods in one location and an equal basket of goods in another location.

So if we considered purchase price parity in the per capita GDP calculations, we will notice Japanese growth simply wavered during the 1990s.