Coinciding with this decrease in trade, the Reserve Bank's Trade Weighted Index (TWI) was at a record level in July 2007, up over 20 percent on July 2006. The TWI is a weighted measure of the value of the New Zealand dollar relative to the currencies of New Zealand’s major trading partners. An increased dollar value has a downward influence on prices for both exports and imports, which may be related to some of the decreases in commodity trade values.
In July 2007, commodity groups showing large decreases in trade value included aircraft and parts, which was down for both imports and exports, primarily due to high-value aircraft traded in the previous July. Imports of petroleum and products also decreased considerably, while the most significant decrease in exports was seen in meat and edible offal.
Showing the largest increase in imports from a year before, vehicles, parts and accessories were up $81 million (21.6 percent) in July 2007, with motor cars accounting for two-thirds of this increase.
The trade balance was a deficit of $791 million, the largest on record for a July month. Equivalent to almost a third of all exports, this deficit is the highest proportion of exports for a July month since 1976. All July months in the last 10 years have shown a deficit, with an average of $363 million.