The Opposition parties' inquiry finds major "fissures" in the sector.
“Capital destruction on such a scale will severely undermine business confidence,” open letter says.
The PMI has emerged from a four-month contraction, the longest consecutive monthly fall since 2009.
Business NZ welcomes a government report focusing on ways to improve overseas competitiveness.
"For now, uncertainty is the new certainty," economist John Pask says.
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