Organic agriculture

PREFIX sdmx-measure: <http://purl.org/linked-data/sdmx/2009/measure#> 
PREFIX sdmx-dimension: <http://purl.org/linked-data/sdmx/2009/dimension#> 
PREFIX property: <http://rdfdata.eionet.europa.eu/eurostat/property#> 
PREFIX rdf-schema: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX geo: <http://rdfdata.eionet.europa.eu/eurostat/dic/geo#>

SELECT 
bif:either(?geo = geo:DE, 'Germany', ?ugeo) as ?country
sum(xsd:decimal(?2000)) as ?2000
sum(xsd:decimal(?2006)) as ?2006
sum(xsd:decimal(?2012)) as ?2012

( sum(xsd:decimal(?2012)) - sum(xsd:decimal(?2006)) ) as ?change

WHERE {
{  
  GRAPH <http://rdfdata.eionet.europa.eu/eurostat/data/food_in_porg1.rdf.gz> 
  {
   _:food_in_porg1 property:geo ?geo .
   _:food_in_porg1 property:cropitem <http://dd.eionet.europa.eu/vocabulary/eurostat/cropitem/C_00> .
   _:food_in_porg1 property:variable <http://dd.eionet.europa.eu/vocabulary/eurostat/variable/PCT_ORG_UAA> .

   {
    _:food_in_porg1 sdmx-dimension:timePeriod ?date . FILTER (year(?date) = 2000)
    _:food_in_porg1 sdmx-measure:obsValue ?2000 .
   } UNION {
    _:food_in_porg1 sdmx-dimension:timePeriod ?date . FILTER (year(?date) = 2006)
    _:food_in_porg1 sdmx-measure:obsValue ?2006 .
   } UNION {
    _:food_in_porg1 sdmx-dimension:timePeriod ?date . FILTER (year(?date) = 2012)
    _:food_in_porg1 sdmx-measure:obsValue ?2012 .
   }
  } 
  ?geo rdf-schema:label ?ugeo . FILTER (?geo != geo:NO and ?geo != geo:CH and ?geo != geo:MK and ?geo != geo:EL and ?geo != geo:CY)
}
} 
GROUP BY ?geo ?ugeo
ORDER BY ?ugeo