In principle, the EU Agricultural Council may change the reference intervention prices in the light of developments in production and the markets. Governmental purchases may be replaced by aids for private storage. As administrational cuts to intervention prices were difficult to achieve in the past and, as intervention prices above the respective equilibrium induced production growth and stock building, a tendering system for butter was implemented in 1987 and SMP intervention purchases were limited to 109000 tonnes. Since March 2004 a further change has meant that butter can only be purchased for intervention when prices are below 92% of.
