Although price premiums were 29 to 32%, breakeven premiums necessary for organic profits to match conventional profits were only 5 to 7%, even with organic yields being 10 to 18% lower. The size of organic premiums awarded, and the difference between
organic premiums and breakeven premiums, were consistent during the 40-year study period. The fact that organic premiums were significantly higher than breakeven premiums suggests that organic agriculture can continue to expand even if premiums decline. The
study also found that total costs were not significantly different, but labour costs were significantly (7 to 13%) higher with organic farming practices20. Although one of the successes of conventional agriculture has been its ability to produce more with less labour, some
have found the extra labour of organic agriculture to be beneficial in providing rural employment and development opportunities62,63. Few economic studies have accounted for negative externalities (such as environmental costs) or positive externalities (such as ecosystem services), with associated monetary values, in organic and conventional comparison studies. Putting a price on the negative externalities caused by farming, such as soil erosion or nitrate leaching into groundwater, would make organic agriculture even more profitable, given that its environmental impact is less than that of conventional agriculture45–58. Indeed, it has been estimated that a switch to organic production would lower the external costs of agricultural production in the United Kingdom by 75%, from £1,514 million yr–1 to £385 million yr–1 (ref. 64).