Complex sentence: The country underwent major economic changes during the 1980s, which transformed it from a protectionist to a liberalised free trade economy; once-dominant exports of wool have been overtaken by dairy products, meat, and recently wine.
Split into simpler sentences: The country underwent major economic changes during the 1980s, which transformed it from a protectionist to a liberalised free trade economy. Markets for New Zealand's agricultural exports have diversified greatly since the 1970s, with once-dominant exports of wool being overtaken by dairy products, meat, and recently wine.