To find out the number of Japanese yen they can receive for each New Zealand dollar, traders can check the NZD/JPY Spot price.
If the number increases over a period of time, this indicates that the NZ dollar is getting stronger in comparison with the yen.
The NZ dollar tends to fluctuate according to the economic, political and commercial situation in the country.
It is also susceptible to changes in the prices of commodities such as base metals and - as New Zealand is a net food exporter - the value of agricultural products.
While the dollar - or Kiwi as it is sometimes referred to - is only the tenth most-traded currency in the world, when you bear in mind the nation's GDP and population size, this is a relatively high position.
The yen is the third most-traded currency in the world and its value is influenced by official reports such as interest rate changes, inflation, unemployment and trade balance.
In order to maintain a steady rate of economic growth, the Bank of Japan will intervene if the money gets too strong, a possibility that traders are aware of and that can act as a downward pressure on the currency's value.
The price of commodities like coal, oil and aluminium can also play an important role, due to the country's manufacturing sector.