Bank of Japan Research and Sascs Deparmen Oulne of he Corporae Goods Prce Index (CGPI, 2010 base) March, 2015 1. Purpose and Applcaon The Corporae Goods Prce Index (CGPI) measures he prce developmens of goods raded n he corporae secor. One of he purposes of he ndex s o grasp he supply and demand condons of ndvdual goods, as well as o provde maeral for he economc assessmen and he moneary polcy decson-makng. Also, he CGPI s used as a deflaor n calculang real values,.e., n removng prce facors from flucuaons n nomnal values, such as n he esmaon of he Naonal Accouns (Cabne Offce). In addon, he CGPI s ced as a reference for he prce-seng acves n he prvae secor. 2. Srucure, Classfcaon and Weghs Commodes are classfed no hree Basc groupng ndexes: Producer Prce Index (PPI), prevously called he Domesc Corporae Goods Prce Index (DCGPI), Expor Prce Index (EPI) and Impor Prce Index (IPI). The Bank of Japan (BOJ) also comples Reference ndexes n whch commodes of he Basc groupng ndexes are reclassfed under dfferen crera for specfc purposes or adjusmens made o he sample prces (see below) of he Basc groupng ndexes. < Basc groupng ndexes > Producer Prce Index (PPI) For he PPI, he BOJ surveys prces of domescally-produced and domescally-raded goods n he corporae secor, manly a he me of shpmen by producers. The weghs are calculaed usng value of ransacons (whch are obaned by deducng he expor value of 2010 n he Trade Sascs of Japan by Mnsry of Fnance from oal shpmens of 2010 n he Census of Manufacures by Mnsry of Economy, Trade and Indusry). As for weghs whch canno be calculaed from he above sources (such as non-manufacurng producs), he BOJ uses oher sascs publshed by governmen agences or ndusry organzaons accordngly. The PPI s classfed no 5 major groups and furher classfed no 23 groups; s compled ncludng he consumpon ax. Expor Prce Index (EPI) & Impor Prce Index (IPI) Prces of expors from Japan are surveyed for he EPI, whle hose of mpors o Japan are used for he IPI. The ndexes are publshed on boh a yen bass and a conrac currency bass. The value of expors and mpors of 2010 (from he Trade Sascs of Japan by Mnsry of Fnance) are used for calculang he weghs. The EPI and IPI are classfed no 7 groups and 10 groups, respecvely. < Reference ndexes > Index by Sage of Demand and Use (ISDU) Ths ndex s compled by reclassfyng he PPI excludng he consumpon ax (see below), EPI and IPI n erms of commodes sage of demand or use of goods. I s used o analyze varous prce developmens, such as how a prce change n one sage affecs ha n oher sages. Producer Prce Index usng Chan-weghed Index Formula (Chan-weghed PPI) Ths ndex recalculaes he PPI usng he chan-weghed Laspeyres formula. Weghs are chan-lnked, whch allows he weghs o change annually (every December). I s compled ncludng he consumpon ax.
Producer Prce Index excludng Consumpon Tax (PPI excludng consumpon ax) Ths ndex s compled usng prces excludng he consumpon ax. Prewar Base Index (PBI) Ths ndex s compled by rearrangng he Basc groupng ndexes and ISDU n conssen wh he Prewar Base Index classfcaon (whch consss of he basc groupng and he specal groupng by use of goods). Sandard passenger cars (for Norh Amerca) & Sandard passenger cars (for he res of he world) These ndexes are compled by recaegorzng sample prces of Sandard passenger cars n he EPI by desnaon. 3. Base Year for Index and Wegh Calculaon The calendar year 2010 s used as he base year for boh he ndexes and wegh calculaon. 4. Selecon of Commodes < Commody Selecon Procedure > PPI The BOJ selecs each commody wh a ransacon value of no less han 1/10,000 (21.4 bllon yen for he 2010 base PPI) of he oal ransacon value for he ndex (.e. he oal value of shpmens of domesc goods for he domesc marke) n he base year. EPI and IPI The BOJ selecs each commody wh a ransacon value of no less han 5/10,000 (30.1 bllon yen and 28.5 bllon yen for he 2010 base EPI and IPI, respecvely) of he oal ransacon values for he ndexes (.e. he oal value of expors and mpors) n he base year. < Number of Seleced Commodes > The number of seleced commodes s 822 for he PPI, 210 for he EPI and 254 for he IPI. 5. Sample Prces < Basc Prncples of Prce Survey > The basc daa used for complng he ndvdual commody ndexes n he CGPI are he surveyed prces referred o as sample prces. An deal sample prce s he one whch represens he mporan ransacon of he commody and reflecs pure prce change wh he same specfcaon, sales condon, and so on. < Sage and Tmng of Prce Collecon > The sandard for he sage and mng of prce collecon s unfed a he me of shpmen by producers (such prces are somemes called facory gae prces ) for he PPI, whle he sandard for he sage and mng of prce collecon for he EPI and IPI s unfed a he me cargo s loaded/unloaded n Japan a he cusoms clearance sage. In prncple, he FOB (free on board) prces a he Japanese por of expor are surveyed for he EPI and he CIF (cos, nsurance, and fregh) prces a he Japanese por of mpor are surveyed for he IPI. For he PPI, he rao of sample prces ha are colleced a he producer sage has been ncreased from 84% for he 2005 base ndex o 91%. < Prce Survey Procedure > A he begnnng of every monh, companes are requesed o repor he sample prce of he prevous monh. The sample prces of foregn-currency-based ransacons are recorded on an orgnal conrac currency bass. In complng ndexes on a yen bass, he sample prces n he conrac currency are convered no her yen equvalens usng he monhly average spo exchange raes (TTM: Telegraphc Transfer Mddle Rae).
< Treamen of mssng prces > If no prce repor was receved for a parcular monh, he changes n he sample prce wll, n prncple, be assumed o reman unchanged from he prevous monh. However, he sample prces of foregn-currency-based ransacons reflec he exchange rae for he curren survey monh when convered no a yen bass. < Prcng Mehods > The drec use of prces of repeaed ransacons s he basc prcng mehod for he CGPI. However, oher prcng mehods such as he un value mehod or he markup mehod are also used when he drec use of prces of repeaed ransacons s no applcable for capurng acual prce developmens. In general, ls prce survey s consdered o be he las resor. < Ulzaon of Provsonal Prces > When a conrac lass for several monhs (quarerly, b-annual conracs, ec.), and a shpmen prce s deermned only afer he conrac has begun (or ndeed afer he conrac has ermnaed), he ndex s composed usng provsonal prces (he nerm prces used unl he fnalzed prces are deermned) when avalable. These prces, whch should be accurae up o a pon, are used unl he ndex s revsed based on he fnalzed prces when he reroacve ndex revson s scheduled. < Adopon of Prces from Oher Sascs and Daabases > In some ndexes, he BOJ apples prces from oher sascs and daabases, whch are regarded o be accurae, cos-effcen, and avalable connuously. < Sample Prce Replacemen and Qualy Adjusmen Mehod > The relevan sample prce s replaced whou delay n cases: (1) when one of he servces ceases o be a represenave n he marke of he em concerned; (2) when here s a change n conrac erms; and (3) when becomes necessary o replace he reporng company for some reason. When replacng a sample prce, he BOJ res o adjus any dfference beween he old and new sample prces usng he qualy adjusmen mehod so ha he ndex reflecs pure prce changes. One of he followng fve qualy adjusmen mehods are used for replacemen: he drec comparson mehod; he un prce comparson mehod; he producon cos mehod; he overlap mehod; and he hedonc regresson mehod. The hedonc regresson mehod one of he qualy adjusmen mehods based on economerc analyss esmaes he prces of new producs by he regresson funcon of her characerscs. Ths mehod esmaes he funconal relaonshp beween he characerscs and prces of producs n he marke. I yelds esmaes of he value of he produc s qualy change ha may be used o value he qualy mprovemen resulng from changes n varous characerscs of he produc. The value of he qualy change can hen be removed from he repored prce change o measure he pure prce change ha s approprae for he CGPI. The hedonc regresson mehod s currenly appled o 5 IT-relaed commodes wh shor produc cycles and a sgnfcan qualy mprovemen accompaned by echnologcal nnovaon: servers, personal compuers, compuer prners, dgal cameras, vdeo cameras. 6. Index Formula Fx-weghed Laspeyres Formula The fx-weghed Laspeyres formula, whch s a weghed arhmec mean based on fxed value-based weghs se n he base perod, s adoped for he ndex calculaon. Fx-weghed Laspeyres formula: p q p L, 0,, P 0, w0, p0, q0, p0,
L P 0, :prce ndex n perod relave o base perod 0, compled usng he fx-weghed Laspeyres formula, p, :prce of commody n perod, p 0, :prce of commody n base perod 0, w 0, :value-based wegh of commody relave o he oal value of all commodes, fxed n base perod 0, q 0, :quany of commody n base perod 0. Chan-weghed Laspeyres Formula The PPI usng Chan-weghed Index adops he chan-weghed Laspeyres formula, whch s he weghed arhmec mean based on he chaned value-based weghs. Chan-weghed Laspeyres formula: CP 0 : 1: ~ P L 0, m, m CP 1,12 1 ~, m where, CP, : prce ndex for monh m, year, compled usng he chan-weghed Laspeyres formula, m ~ L : fx-weghed Laspeyres ndex for monh m, year 0, usng year 0 wegh (Geomerc mean s P 0,m appled for he aggregaon of sample prces o commody level). ~ : rae of change n he chan-weghed Laspeyres ndex from December, year -1 o monh m, year. Here, ~ s calculaed by he followng formula:, m 1 ~ 1, ~, m, w m 1 N where, ~ : rae of change n he commody ndex from December, year -1 o monh m, year, w 1 : relave wegh of he commody n year -1( w 1), N 1, and ~ s defned as: j ~ j w 1 w 1 1,, m, m j 1 j : rae of change n he sample prce ndex from December, year -1 o monh m, year, j w 1 : relave wegh of he sample prce n year -1( j j w w 1). 1 1 7. Publcaon The prelmnary fgure ndexes are released a 8:50 on he eghh workng day of he monh followng he survey monh. The fnalzed fgures are released n lne wh he nex monh s prelmnary fgure ndexes. A number of secury measures are aken n order o proec he confdenaly of reporng companes. For example, each commody ndex s, n prncple, compled usng a leas hree sample prces suppled from plural companes unless specal approvals are obaned from all he reporng companes nvolved. Also he BOJ may ermnae he publcaon of an ndex or ndexes of specfed commodes when s regarded necessary o proec he confdenaly of reporng companes. Scheduled reroacve revsons are made o he released ndexes wce a year (n Aprl and Ocober, along wh he release of he prelmnary fgures for he March and Sepember ndexes). Scheduled reroacve
revsons cover, n prncple, he mos recen 18 monhs worh of ndexes. In addon o he scheduled reroacve revsons, unscheduled revsons are conduced when a change n he fgures whch have a sgnfcan mpac on he overall ndex (such as he one resulng n changes a he ndex level of All commodes) s revealed afer he release; hey are hen revsed as soon as possble. 8. Lnked Indexes < 2010 Base Lnked Indexes > The 2010 Base Lnked Index offers a reroacvely compled seres of he Basc groupng and Reference ndexes for commody, group, and hgher-order classfcaons (or equvalen hgher-order classfcaons n Reference ndexes). < Prewar Base Index (PBI) > The PBI s acheved by rearrangng and re-basng he 2010 base PPI, EPI, IPI and ISDU o conform o he PBI groupngs. The base perod s he 1934-1936 average (= 1); here are 12 groups n he Basc groupng and 5 caegores n he Specal groupng (by use of goods).