The trade deficit widened to $2.2 billion in the year ended February, the biggest it has been since August 2009.
Exports last month at $3.9 billion were 13 per cent lower than in February last year under the weight of a 41 per cent or $900 million drop in dairy exports, three-quarters of which reflected lower prices rather than volumes.
Last month's exports exceeded imports, which were up 3.7 per cent on February last year, by just $50 million.
The annual deficit of $2.2 billion was up from a deficit of $1.4 billion in the year ended January.
Most of it, $1.3 billion, reflected imports of "large items" - those worth more than $100 million.
New Zealand imported $2 billion worth of aircraft in the latest year, $1.1 billion more than the year before.
Among the major commodities, dairy exports were down $1.1 billion or 7.5 per cent in the year ended February.
But that was almost matched by a $1 billion decline in the cost of oil imports, and meat exports were up $700 million.
Imports of capital plant and machinery last month were 13.4 per cent higher than in February last year, while for the year ended February they were up 5.1 per cent on the year before.
Imports of consumer goods were up 14 per cent and 4.6 per cent respectively, and cars 11.2 per cent and 8.8 per cent respectively.
Exports to China dropped $2 billion to $8.9 billion over the past year. However, it remains the largest export destination, just ahead of Australia.
In the year ended February trade with China was almost exactly in balance.
Exports to the United States, the third largest national market, rose $1 billion to $5 billion in the latest year, while imports from the US rose $1.5 billion to $6 billion.
ASB economists in a note on the trade data said they expected the trade balance to trend sideways over the rest of the first half of 2015 as low oil prices and recovering dairy prices balanced otherwise growing import values.
"Later in 2015, we expect growing import demand, reflecting solid domestic activity, to more than offset recovering dairy export prices and lead to wider trade deficits," they said.
• $2.2 billion annual trade deficit
• $2 billion of aircraft imports
• $8.9 billion of exports to China
• $5 billion of exports to the United States