REPRESENTATIVE RATES . FURTHER , THE CONCEPT OF ADJUSTMENT OF AGRICULTURAL PRICES WITHIN THE MEANING OF ARTICLE 1 OF REGULATION NO 1134/68 COVERS ONLY AN ADJUSTMENT WHICH THE COUNCIL DECIDES TO MAKE WHEN DEALING WITH AN ALTERATION IN THE VALUE OF THE UNIT OF ACCOUNT FOLLOWING AN ALTERATION IN THE PARITY OF THE CURRENCY OF ONE OR MORE MEMBER STATES . THAT CONCEPT THUS DOES NOT COVER DECISIONS IN RELATION TO PRICES SUCH AS THOSE TAKEN ON 6 APRIL 1981 ON THE BASIS OF THE AGRICULTURAL REGULATION AS PART OF THE ANNUAL REVIEW OF AGRICULTURAL PRICES .
11 IN THAT RESPECT IT MUST BE REMEMBERED THAT ARTICLE 1 OF REGULATION NO 1134/68 GIVES A RIGHT TO CANCELLATION OF THE ADVANCE FIXING OF INTER ALIA EXPORT REFUNDS AND THE RELEVANT CERTIFICATE IN TWO CASES , NAMELY ON THE ONE HAND ' ' IN THE CASE OF AN ALTERATION TO THE VALUE OF THE UNIT OF ACCOUNT ' ' AND ON THE OTHER IN THE CASE OF ' ' AN ADJUSTMENT OF AGRICULTURAL PRICES PURSUANT TO THE FOURTH PARAGRAPH OF ARTICLE 3 OF REGULATION ( EEC ) NO 653/68 ' ' . ARTICLE 4 ( 1 ) THEREOF GIVES A RIGHT TO CANCELLATION MOREOVER ' ' IN THE CASE OF AN ALTERATION OF THE RELATIONSHIP BETWEEN THE PARITY OF THE CURRENCY OF A MEMBER STATE AND THE VALUE OF THE UNIT OF ACCOUNT ' ' .
12 IN THE FIRST PLACE , IN SO FAR AS THE QUESTIONS RELATE TO THE CURRENCY ALTERATIONS WHICH OCCURRED ON 23 MARCH 1981 IT MUST BE OBSERVED THAT THE AFORESAID PROVISIONS REFER EXPRESSLY ONLY TO ALTERATIONS IN THE VALUE OF THE UNIT OF ACCOUNT OR IN THE RELATIONSHIP BETWEEN THAT VALUE AND THE PARITY OF THE CURRENCY OF A MEMBER STATE .
13 FURTHER , THE AFORESAID PROVISIONS OF REGULATION NO 1134/68 ARE INTENDED TO ALLOW THE COMMUNITY INSTITUTIONS AND THE COMPETENT NATIONAL AUTHORITIES TO TAKE THE APPROPRIATE MEASURES TO DEAL WITH CURRENCY ALTERATIONS WHICH HAVE A DIRECT EFFECT UPON AGRICULTURAL PRICES . THAT IS NOT THE CASE , HOWEVER , WITH ALTERATIONS IN THE VALUE OF THE ECU OR THE CURRENCIES COMPOSING IT , BECAUSE SINCE THE ENTRY INTO FORCE OF COUNCIL REGULATION NO 878/77 OF 26 APRIL 1977 AGRICULTURAL PRICES HAVE CEASED TO DEPEND ON THE OFFICIAL PARITIES AND CENTRAL RATES OR EFFECTIVE EXCHANGE RATES RESPECTIVELY AND ARE BASED ON THE REPRESENTATIVE RATES OF THE NATIONAL CURRENCIES , WHICH IN THE PRESENT CASE REMAINED UNCHANGED DURING THE PERIOD FROM 23 MARCH TO 5 APRIL 1981 . UNDER THE PRESENT SYSTEM SET UP BY THE AFORESAID REGULATIONS NOS 878/77 AND 652/79 THE CONVERSION OF THE ECU INTO A NATIONAL CURRENCY FOR THE PURPOSES OF THE COMMON AGRICULTURAL POLICY IS MADE ON THE BASIS OF THE REPRESENTATIVE RATES , THE DIFFERENCE IN WHICH IN RELATION TO THE CENTRAL RATES AND EFFECTIVE EXCHANGE RATES RESPECTIVELY IS COMPENSATED FOR BY THE PAYMENT OF MONETARY COMPENSATORY AMOUNTS .
14 THAT CONCLUSION IS CONFIRMED BY THE FACT THAT ARTICLE 4