1. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA Nadiežda Alejeva Head, Price Statistics Division Statistics Lithuania 1

2. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN CONTENT OF THE PRESENTATION  HARMONISATION OF THE NATIONAL CONSUMER PRICE INDEX (CPI)  PRICE COLLECTION PROCEDURE  REORGANISATION OF THE PRICE DATA COLLECTION PROCEDURE  THE ASSURANCE OF DATA QUALITY 22

3. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN HARMONISED CONSUMER PRICE INDEX (HICP)  CANDIDATE COUNTRIES (CCs), ON ENTERING EUROPEAN UNION (EU) MEMBERSHIP, ARE REQUIRED TO IMPLEMENT THE “AQUIS COMMUNAUTAIRE” DURING THE PRE-ACCESSION STAGE AND THE IMPLEMENTATION OF HICPs IS AMONG THE COMMITMENTS CONCERNED.  CCs MUST IMPLEMENT THE REQUIREMENTS AND MINIMUM STANDARDS OF THE EUROPEAN COUNCIL AND THE EUROPEAN COMMISSION REGULATIONS CONCERNING THE COMPILATION OF THE HICP (THERE ARE 19 REGULATIONS AT THE MOMENT).  CCs ARE SUPPOSED TO GET COMPLETELY READY TO COMPILE AND RELEASE MONTHLY HICPs BEFORE THE INTEGRATION INTO THE EU STATISTICAL SYSTEM.  SUBSTANTIAL PREPARATION IS REQUIRED BEFORE IMPLEMENTATION OF THE HICP REGULATIONS. 33

4. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN THE CPI HARMONIZATION PROCESS (INTERIM HICP)  IN LITHUANIA, THE PROCESS OF THE HARMONIZATION OF THE CPI WAS STARTED IN 1997.  PROCESS OF THE IMPLEMENTATION OF THE PRINCIPAL REQUIREMENTS, METHODS AND RULES AS WELL AS THE INTERIM HICP PRODUCTION TOOK SEVERAL YEARS.  REPORTS ON THE PROGRESS OF THE CPI HARMONIZATION WERE PERIODICALLY PRESENTED AND DISCUSSED AT THE MEETINGS OF THE SENIOR MANAGEMENT COMMITTEE.  A REGULAR PROVISION OF THE INTERIM ALL-ITEMS HICP AND SUB- INDICES BY 12 COICOP/HICP DIVISIONS TO EUROSTAT HAS BEEN ESTABLISHED SINCE 1999.  SINCE 2003, STATISTICS LITHUANIA HAS BEEN COMPILED THE HICP COMPATIBLE WITH THAT OF THE EU MEMBER STATES AND TRANSMITTED THE DATA TO EUROSTAT AS WELL AS PUBLISHED IT IN OFFICIAL PUBLICATIONS.  THE HICP HAS BEEN RELEASED IN LITHUANIA SINCE JULY 2003.  ASSESSMENT OF THE HICP COMPLIANCE WAS CARRIED OUT BY EUROSTAT IN 2004.  LITHUANIA ENTERED THE EU IN MAY 2004. 44

5. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN THE HICP COMPUTATION, ANALYSIS, PUBLICATION  THE HICP IS PRODUCED BY STATISTICS LITHUANIA USING A HARMONIZED METHODOLOGY. THE METHODS, PROCEDURES AND FORMULAE USED FOR THE HICP COMPILATION ENSURE COMPARABILITY REQUIREMENTS.  THE NORMAL CPI/HICP PRODUCTION PROCESS CONSISTS OF THE FOLLOWING PHASES: PRICE DATA COLLECTION BY PRICE COLLECTORS AND CENTRAL STAFF; PRIMARY PRICE DATA VERIFICATION AS WELL AS APPROPRIATE ADJUSTMENTS AND IMPUTATIONS IN CASES OF CHANGES IN QUALITY AND MISSING PRICES; PROCESSING AND VALIDATION; CALCULATION OF SUB-INDICES AND ALL-ITEMS INDEX; DISCUSSION OF THE PRELIMINARY CPI/HICP RESULTS DURING THE MONTHLY MEETINGS OF THE CONSUMER PRICE STATISTICS STAFF; 5

6. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN THE HICP COMPUTATION, ANALYSIS, PUBLICATION CROSSCHECKING AGAINST THE PRODUCER PRICE INDEX, SERVICES PRICE INDEX AND INFORMATION RECEIVED FROM OTHER INSTITUTIONS AS WELL AS OTHER SOURCES; CALCULATION OF THE FINAL CPI AND HICP, PREPARATION OF THE SUMMARY TABLES AND PRESS RELEASES AS WELL AS OTHER PUBLICATIONS; OBTAINING THE AGREEMENT OF SENIOR MANAGEMENT TO PUBLISH PRESS RELEASES AND TRANSFER TO THE PUBLIC RELATIONS DIVISION; DISSEMINATION OF PRESS RELEASES ON THE CPI AND HICP THROUGH THE MASS MEDIA ACCORDING TO THE LIST (BY THE PUBLIC RELATIONS DIVISION); MAKING THE HICP DATA AVAILABLE ON THE WEBSITE, IN THE DATABASE OF INDICATORS (BY DISSEMINATION STATISTICAL INFORMATION DIVISION); SIMULTANEOUS TRANSMISSION OF THE HICP DATA TO EUROSTAT (BY THE PRICE STATISTICS DIVISION). 66

7. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN THE HICP COMPUTATION, ANALYSIS, PUBLICATION  THE REGULAR HICP AND HICP INFLATION FORECAST ARE RELEASED EACH MONTH AT PRE-ANNOUNCED DATES BY STATISTICS LITHUANIA IN MONTHLY PRESS RELEASES.  FURTHERMORE, STATISTICS LITHUANIA COMPILES AND PUBLISHES A NUMBER OF SO-CALLED ‘SPECIAL AGGREGATES’ FOR GROUPS OF PRODUCTS THAT ARE OF PARTICULAR INTEREST TO ECONOMIC ANALYSIS.  A SEPARATE PRESS RELEASE OF THE HICP HAS BEEN PUBLISHED SINCE FEBRUARY 2006.  THE CPI IS RELEASED ON THE 6 TH WORKING DAY (IN FEBRUARY – ON THE 10 TH WORKING DAY) AFTER THE END OF THE REFERENCE MONTH AT 11:00 a.m.  THE HICP IS RELEASED ON THE 7 TH WORKING DAY (IN FEBRUARY – ON THE 14 TH WORKING DAY) AFTER THE END OF THE REFERENCE MONTH AT 11:00 a.m.  THE HICP INFLATION FORECAST IS RELEASED ON THE 12 TH WORKING DAY AFTER THE END OF THE REFERENCE MONTH AT 11:00 a.m. 77

8. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN MONTHLY PRESS RELEASE ON THE CPI/HICP  PRESS RELEASES ARE AVAILABLE IN LITHUANIAN AND ENGLISH.  THE CPI/HICP DATA ARE RELEASED SIMULTANEOUSLY TO ALL INTERESTED PARTIES AND POSTED ON THE WEBSITE OF STATISTICS LITHUANIA.  PRE-RELEASE ACCESS IS GRANTED TO THE PRIME MINISTER OF THE REPUBLIC OF LITHUANIA, MINISTER OF FINANCE, MINISTER OF ECONOMY, MINISTER OF SOCIAL SECURITY AND LABOUR OR THEIR AUTHORIZED PERSONS HALF AN HOUR BEFORE THE RELEASE TIME. 88

9. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN ORGANISATION OF WORK IN STATISTICS LITHUANIA  BOTH, THE LOCAL AND THE CENTRAL STAFF ARE INVOLVED IN THE CPI/HICP PRODUCTION PROCESS: 10 CENTRAL STAFF MEMBERS WORKING ON THE CPI AND HICP; 26 LOCAL STAFF MEMBERS – PRICE COLLECTORS – CARRY OUT PRICE COLLECTION IN 18 TERRITORIAL UNITS (10 COUNTIES AND 8 REGIONAL CENTRES) IN 3900 SELECTED OUTLETS:  3 PRICE COLLECTORS IN CAPITAL CITY – VILNIUS;  2 PRICE COLLECTORS IN EACH OF 4 BIGGEST CITIES OF LITHUANIA;  15 PRICE COLLECTORS IN OTHER TERRITORIAL UNITS. 9

10. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN ORGANISATION OF WORK IN STATISTICS LITHUANIA  RESPONSIBILITIES OF THE CENTRAL STAFF: YEARLY WORKS OUT THE TIMETABLE FOR THE COLLECTION AND TRANSMISSION OF THE PRIMARY DATA ON PRICES FOR PRICE COLLECTORS; PREPARES AND ANNUALLY CARIES OUT REVIEW AND UPDATE OF THE ‘BASKET’ OF REPRESENTATIVE GOODS AND SERVICES; IS PARTIALLY INVOLVED IN THE PRICE COLLECTION PROCESS; CARRIES OUT THE SECONDARY VERIFICATION OF THE PRIMARY DATA RECEIVED FROM PRICE COLLECTORS; CARRIES OUT THE APPROPRIATE ADJUSTMENTS AND IMPUTATIONS IN CASES OF QUALITY CHANGES AND MISSING PRICES, ESTIMATION OF SEASONAL PRODUCTS PRICES IN OUT-OF-SEASON PERIOD; PREPARES THE WEIGHTINGS SYSTEM AND PERFORMS THE CALCULATION OF THE CPI AND THE HICP; PREPARES PRESS RELEASES, PUBLICATIONS, OTHER STATISTICAL INFORMATION; ELABORATES METHODOLOGICAL DOCUMENTS; ORGANISES TRAINING OF THE LOCAL STAFF AND INSPECTION OF THEIR WORK. 10

11. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN ORGANISATION OF WORK IN STATISTICS LITHUANIA  RESPONSIBILITIES OF THE LOCAL STAFF – PRICE COLLECTORS: TO SELECT THE OUTLETS WHERE PRICES OF CONSUMER GOODS AND SERVICES WILL BE COLLECTED; TO SELECT SPECIFIC VARIETIES OF REPRESENTATIVE PRODUCTS WITHIN AGREED DEFINITIONS IN THE OUTLETS; TO REGISTER PRICES THROUGH MONTHLY VISITS TO SELECTED OUTLETS; TO COLLECT PRICES ADMINISTRATED BY LOCAL AUTHORITIES (FROM LEGAL ACTS); TO EXPLORE THE REASONS OF SIGNIFICANT CHANGES IN PRICES; TO EVALUATE THE PRICE CHANGE DUE TO THE QUALITY CHANGE; TO SEND THE PRICE DATA AND INFORMATION ON THE DETAILS ON CHANGES IN CHARACTERISTICS OF GOODS AND SERVICES TO THE CENTRAL STATISTICAL OFFICE; TO FOLLOW THE MARKET DEVELOPMENT. 11

12. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN PRICE COLLECTION PROCEDURE  THERE ARE TWO APPROACHES TOWARDS PRICE COLLECTION: PRICE COLLECTION BY THE CENTRAL STAFF (2280 PRICE QUOTATIONS (3%) OF 29 PRODUCTS (3%)):  FOR GOODS THAT ARE TECHNICALLY COMPLICATED;  FOR GOODS AND SERVICES FOR WHICH SPECIAL SUB-INDICES ARE CALCULATED;  PRICES WHICH ARE ADMINISTRATED BY THE CENTRAL GOVERNMENT OR THE NATIONAL REGULATOR;  PRICES THAT ARE THE SAME ACROSS THE ENTIRE COUNTRY; PRICE COLLECTION BY PRICE COLLECTORS AT THE LOCAL LEVEL (68400 PRICE QUOTATIONS (97%) OF 873 PRODUCTS (97%)):  MARKET PRICES OF CONSUMER GOODS AND SERVICES;  PRICES WHICH ARE ADMINISTRATED BY THE LOCAL GOVERNMENT. 12

13. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN PRICE COLLECTION PROCEDURE  PRICE DATA SOURCES: REGISTRATION OF PRICES CARRIED OUT BY PRICE COLLECTORS THROUGH VISITING THE SELECTED OUTLETS; LEGAL ACTS: GOVERNMENT DECREES, REGULATIONS AND ORDERS, DECISIONS OF THE NATIONAL REGULATOR, ETC.; INTERNET WEBSITES OF OTLETS; CATALOGUES, PRICE LISTS AND ADVERTISEMENTS.  PRICE DATA COLLECTION TECHNIQUES: HAND-HELD COMPUTERS; INTERNET; TELEPHONE INQUIRIES; ELECTRONIC QUESTIONNAIRE; PAPER QUESTIONNAIRE. 13

14. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN REORGANISATION OF THE PRICE DATA COLLECTION PROCEDURE  REORGANISATION WAS ACCOMPLISHED DUE TO A NECESSITY TO IMPLEMENT THE PROVISIONS OF COUNCIL REGULATION (EC) No 701/2006 OF 25 APRIL 2006 AS REGARDS THE TEMPORAL COVERAGE OF PRICE COLLECTION IN THE HICP: PRICE COLLECTION HAS TO TAKE PLACE ACROSS AT LEAST ONE WORKING WEEK PERIOD AT, OR NEAR, THE MIDDLE OF THE CALENDAR MONTH TO WHICH THE INDEX PERTAINS; WHERE PRODUCTS ARE KNOWN TO TYPICALLY SHOW SHARP AND IRREGULAR PRICE CHANGES WITHIN THE SAME MONTH, PRICE COLLECTION HAS TO TAKE PLACE OVER A PERIOD OF MORE THAN ONE WORKING WEEK:  THIS RULE HAS TO BE APPLIED IN PARTICULAR TO THE FOLLOWING PRODUCTS: ENERGY PRODUCTS, FRESH FOOD, SUCH AS FRUIT AND VEGETABLES. 14

15. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN REORGANISATION OF THE PRICE DATA COLLECTION PROCEDURE  SINCE DECEMBER 2007, THE NEW PRICE COLLECTION PROCEDURE HAS BEEN ESTABLISHED: THE TIMETABLE OF THE PRICE DATA COLLECTION IN SELECTED OUTLETS IS SCHEDULED SEPARATELY FOR EACH TERRITORIAL UNIT; FIXED DAYS FOR THE PRICE COLLECTION PER EACH OUTLET ARE SET IN THE TIMETABLES; MAIN COLLECTION OF THE PRICE DATA COVERS FIRST 14 WORKING DAYS OF THE MONTH; A SAMPLE OF OUTLETS IS EVENLY DISTRIBUTED OVER THREE WEEKS; THE PRICE COLLECTOR SPREADS OUTLETS OVER THE DAYS OF THE WEEK AND AGREES WITH THE CENTRAL STAFF; ONE-THIRD OF ALL PRICE QUOTATIONS IS COLLECTED DURING EACH FIVE WORKING DAYS; PRICES FOR FUELS AND SEASONAL FOOD PRODUCTS ARE ADDITIONALLY COLLECTED DURING THE 15 TH –19 TH WORKING DAYS OF THE MONTH. 15

16. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN TIMETABLE OF THE NEW PRICE COLLECTION PROCEDURE Monday 6132027 Tuesday 7142128 Wednesday 18152229 Thursday 29162330 Friday 3101724 Saturday 4111825 Sunday 5121926 Main price collection Additional price collection for fuels and seasonal food products 16

17. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN REORGANISATION OF THE PRICE DATA COLLECTION PROCEDURE  ADVANTAGES OF THE NEW PRICE DATA COLLECTION PROCEDURE: EACH OUTLET IS VISITED ONCE A MONTH. PRICES OF ALL REPRESENTATIVE PRODUCTS’ VARIETIES, SELECTED IN A PARTICULAR OUTLET, ARE COLLECTED DURING THIS VISIT; THE OUTLETS AND TIME FOR THE PRICE COLLECTION ARE DISTRIBUTED EVENLY; CONVENIENTLY ORGANIZED PRICE COLLECTION ROUTES; PRICE COLLECTORS TRANSMIT THE DATA TO THE CENTRAL DATABASE ON THE DAY WHEN THE DATA COLLECTION TAKES PLACE OR ONE DAY LATER; MORE FREQUENT PROVISION OF THE PRICE DATA TO THE CENTRAL STATISTICAL OFFICE ENABLES THE CENTRAL STAFF TO START THE PRELIMINARY ANALYSIS OF THE DATA AFTER THE FIRST OBSERVATION WEEK. DATA CAN BE USED FOR THE FORECAST; THE CENTRAL STAFF HAS MORE TIME FOR THE DATA VERIFICATION AND EDITING; THE WORKING TIME IS USED BY PRICE COLLECTORS MORE EFFICIENTLY, THE QUALITY OF THE PRICE DATA WAS IMPROVED. 17

18. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN THE ASSURANCE OF DATA QUALITY  THE QUALITY OF PRICE DATA IS THE CRUCIAL DETERMINANT ENSURING THE ACCURACY AND RELIABILITY OF THE CPI AND THE HICP.  PRICE COLLECTORS PLAY THE KEY ROLE IN THE DATA COLLECTION PROCESS.  IN ORDER TO ENSURE THE ADEQUATE QUALITY OF PRICE DATA, THE EXPERIENCE AS WELL AS SOME CERTAIN FEATURES OF PRICE COLLECTORS ARE NEEDED.  PRICE COLLECTORS ARE REQUIRED TO HAVE A COMPREHENSIVE KNOWLEDGE OF THE DATA COLLECTION PROCESS, TO BE COMPUTER LITERATE. 18

19. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN THE ASSURANCE OF DATA QUALITY  CONSIDERABLE ATTENTION IS GIVEN TO PRICE COLLECTORS’ TRAINING: ONE- OR TWO-DAY MEETINGS ARE ORGANIZED FOR PRICE COLLECTORS YEARLY; A PROGRAMME IS DESIGNED TAKING INTO ACCOUNT PRICE COLLECTORS’ WISHES AND QUESTIONS OF THE DAY; PRICE COLLECTORS ARE INSTRUCTED ON:  THE REQUIREMENTS POSED FOR THE PRIMARY DATA OF PRICES;  THE TECHNIQUES THAT CAN BE USED FOR THE REGISTRATION OF PRICES;  THE SELECTION AND REPLACEMENT OF OUTLETS AND VARIETIES OF PRODUCTS;  AN UPDATED LIST OF REPRESENTATIVE PRODUCTS;  COMMON AND FREQUENTLY OCCURRING MISTAKES. CERTAIN SPECIAL SUBJECTS ARE CHOSEN AND EXPERTS ARE INVITED TO ASSIST AND TO EXPLAIN THE CHOSEN SUBJECT THOROUGHLY. 19

20. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN THE ASSURANCE OF DATA QUALITY  OTHER FORMS OF TRAINING OF PRICE COLLECTORS: EVERY YEAR – A ONE-DAY ZONE SEMINAR FOR PRICE COLLECTORS IN ONE OF PARTICULAR COUNTRY ZONE; A SHORT TECHNICAL ASSISTANCE MISSION OF THE CENTRAL STAFF TO ONE TERRITORIAL UNIT.  A MANUAL FOR PRICE COLLECTORS HAS BEEN PREPARED. THE MANUAL PROVIDES PRICE COLLECTORS WITH REQUIREMENTS AND RECOMMENDATIONS AS REGARDS THE PRICE COLLECTION PROCEDURE.  PRICE COLLECTORS ARE EQUIPPED WITH AN ‘M-PATNER’ SYSTEM USERS MANUAL FOR USE OF HAND-HELD COMPUTER.  PRICE COLLECTORS AND THE CENTRAL STAFF COMMUNICATE BY TELEPHONE AND EMAIL ON DIFFERENT PROBLEMATIC ISSUES. 20

21. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN THE ASSURANCE OF DATA QUALITY  CHECKS AGAINST ERRORS AND MISTAKES: SOME CHECKING FUNCTIONS HAVE BEEN INSTALLED IN THE HAND-HELD COMPUTER’S SOFTWARE; PRICE COLLECTORS HAVE ACCESS TO THE CENTRAL DATABASE AND CAN CHECK THE TRANSMITTED DATA; THE CENTRAL STAFF CARRIES OUT THE VERIFICATION OF THE DATA RECEIVED USING THE DATA CONTROL SOFTWARE. 21

22. www.stat.gov.lt HARMONISED CONSUMER PRICE INDEX AND PRICE COLLECTION PROCEDURE IN LITHUANIA WORKSHOP, 13 JULY 2012, YEREVAN THE ASSURANCE OF DATA QUALITY  AS FURTHER MEASURES FOR THE IMPROVEMENT OF PRICE DATA QUALITY IT IS FORESEEN : TO DESIGN AND IMPLEMENT NEW SOFTWARE TO BETTER MANAGE THE ANALYSIS OF THE PRIMARY DATA AT THE CENTRAL LEVEL ; TO ACQUIRE NEW HAND-HELD DEVICES FOR THE PRICE COLLECTION ; FURTHER TO OPTIMISE WORK AS REGARDS THE NUMBER OF PRICES REQUIRED WITHIN EACH ELEMENTARY AGGREGATE ; TO CONSIDER THE POTENTIAL BENEFIT OF THE USE OF ‘SCANNER DATA’ FROM SUPERMARKETS. 22