This graph shows the economic significance to New Zealand of the products derived from grass via sheep and cows – wool, meat and butter. Until the 1890s wool was at times more than half the value of New Zealand’s exports. Then refrigerated shipping made possible first the export of meat, which remained 20–30% of export value until the mid-1980s, and then butter, which was normally over 20% of export value from the early 1920s until 1960. The pastoral sector also exported other products such as skins, cheese and casein, which added to the dominance of the sector.