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Burgernomics to go

該漢堡學閃亮登場了

Using McDonald’s to compare international productivity trends

用麥當勞的數(shù)據(jù)來比較國際生產(chǎn)率變化趨勢

Jun 9th 2012 | from the print edition of The Economist

譯者：終極奔跑者

A MCDONALD’S Big Mac contains 29 grams of fat and a surprisingly large quantity of useful economic information. Since 1986 The Economist has used the ubiquitous sandwich in serving up the Big Mac index, a lighthearted look at currency valuations.

一個麥當勞的巨無霸漢堡包含29克脂肪，還含有多得出乎意料的實用經(jīng)濟學信息?！督?jīng)濟學人》自1986年以來就開始用這種隨處可見的三明治來提供一項巨無霸指數(shù)，這也是一種輕松愉快的貨幣估值方式。

The burgernomics craze is spreading. In a new working paper for the National Bureau of Economics Research, Orley Ashenfelter of Princeton University and Stepan Jurajda of the Charles University in Prague use Big Mac production as a simple but powerful tool for examining productivity and welfare gaps in different economies.

漢堡學的流行正在蔓延開來。在一份新公布的國家經(jīng)濟研究局的工作底稿中，普林斯頓大學的奧利·阿申菲爾特和布拉格查爾斯大學的斯捷潘·尤賴達把巨無霸的生產(chǎn)作為一項簡單而有效的工具，用以研究不同經(jīng)濟體間的生產(chǎn)率和福利差距。

Their work, like The Economist’s Big Mac index, grapples with the tricky business of international price and wage comparisons. At its heart is the theory of purchasing-power parity (PPP). Economists reckon the price of a good should not vary much across efficient markets. Otherwise people would buy in cheap markets and sell in dear ones until prices equalised. PPP generalises this “l(fā)aw of one price”. Over the long run, it suggests, exchange rates should adjust so a basket of goods costs the same in different countries. If that basket is whimsically taken to contain only a Big Mac, then burger prices may be used for back-of-the-napkin currency valuations. In January a Swiss Big Mac cost $6.81, compared with $4.20 in America and just $2.44 in China, hinting at an overvalued franc relative to the dollar and an undervalued yuan.

他們的研究類似經(jīng)濟學人的巨無霸指數(shù)，都是設法解決棘手的國際價格與工資比較問題。其研究核心是購買力平價（PPP）理論。經(jīng)濟學家們認為，在有效市場中，商品價格應該相差不大。否則人們會在低價市場買入商品后在高價市場賣出，直至價格均衡。購買力平價法概括了這條“一價定律”。從長遠來看，這意味著匯率會不斷調(diào)整，使得一籃子商品在不同的國家所費相等。如果異想天開地讓這個籃子里只裝一個巨無霸漢堡，那么我們就會用漢堡的價格在紙巾背面對貨幣進行估值。1月份，一個巨無霸在瑞士售價6.81美元，與之相比在美國售價4.20美元，中國只要2.44美元。這暗示著瑞士法郎相對于美元估值較高，而人民幣估值較美元低。

Economists use PPP to provide better comparisons of welfare across countries than can be gleaned from simply converting wages at market exchange rates. Exchange rates should adjust so that workers making traded goods are paid according to their productivity. But firms that sell non-traded goods and services must compete with firms in the tradable-goods sector for labour. So a country with high-productivity exporting firms will have high wages across all sectors—including those, like hair-cutting, where productivity differences between rich and poor countries are small. As a result, the cost of living is higher in rich countries, and simple exchange-rate adjustments overstate real welfare differences. On an exchange-rate basis, the average American is 35 times richer than the average Indian. On a PPP basis, however, taking account of the lower cost of living in India, American income is just 13 times higher. (The World Bank maintains a PPP database for some 180 countries.)

經(jīng)濟學家利用購買力評價法提供國家間的福利比較，這比簡單地按照市場匯率轉換工資所能收集到的比較結果更好。匯率應該得到調(diào)整，使得生產(chǎn)貿(mào)易品的工人能夠按他們自己的生產(chǎn)力領工資。但是銷售非國際貿(mào)易商品或服務的公司一定會和國際流通商品領域的公司爭搶勞動力。所以在一個擁有眾多高生產(chǎn)率出口公司的國家，所有領域的工資都會很高——包括像理發(fā)這樣富國窮國間生產(chǎn)率差異很小的領域。這樣的話在富裕國家的生活成本會更高，而且單純的匯率校準會夸大實際的福利差距。如果以市場匯率為基礎，普通的美國人比普通的印度人要富裕35倍。然而，如果以購買力平價為基礎，把印度較低的生活成本考慮在內(nèi)的話，美國人的收入僅僅高出印度人13倍。（世界銀行所擁有的約180個國家的數(shù)據(jù)庫都是以購買力平價為基礎的）

Unfortunately, PPP adjustments are hard to calculate. Residents of different countries buy different combinations of goods and services, or similar items with subtle variations in quality. To get around such problems Messrs Ashenfelter and Jurajda focus on a single company. All McDonald’s employees turn similar ingredients into Big Macs, which are more or less identical everywhere (although India’s Maharaja Mac is made from chicken, not beef). Sandwiches are produced according to a rigidly uniform process detailed in a 600-page manual. The company’s reputation depends on its ability to deliver identical burgers in every city: an ideal environment for global productivity comparisons.

遺憾的是，購買力平價的匯率校準很難計算。不同國家的居民會購買不同組合的商品和服務，或是購買只有微小品質(zhì)差別的類似的商品。為了解決這樣的問題，阿申菲爾特先生和尤賴達先生把研究重點集中在一家公司上。麥當勞的所有員工會把相近的食材做成巨無霸漢堡，而且巨無霸在全世界多多少少都是一樣的（盡管印度的王公巨無霸是用雞肉做的，不是用牛肉）。這種三明治會按照一套嚴格統(tǒng)一的生產(chǎn)流程烹飪出來，相關細節(jié)都在一份600多頁的指導手冊中。麥當勞公司憑借其在每一個城市提供相同漢堡的能力而聲譽卓著：這也是比較全球生產(chǎn)率的理想環(huán)境。

To make such comparisons, the authors gather data on McDonald’s wage rates (the McWage) and Big Mac prices. Their efforts began in 1998 in 13 mostly rich countries but have since expanded to include more than 60. Data have been collected annually since 2007, and will be available publicly in future, according to Mr Ashenfelter. Prices and wages are collected from two or more stores in the capital city of smaller countries and from multiple cities in larger ones, including China.

為了進行上述比較，工作底稿的作者們收集了麥當勞工資率（麥工資）和巨無霸的價格兩項數(shù)據(jù)。他們于98年開始在13個最富裕的國家展開工作，至今已擴展到60多個國家。阿申菲爾特先生表示，自2007年起他們每年都會收集相應數(shù)據(jù)，今后這些數(shù)據(jù)將會公開。對較小的國家，價格和工資的數(shù)據(jù)采集自首都的兩家或兩家以上的分店。較大的國家，包括中國，數(shù)據(jù)采集自多個城市。

Supersizing pay rates

超大化的薪酬率

Converting McWages into a common currency generates a surprisingly good picture of international differences in the cost of labour for simple, well-defined tasks. McWages are roughly comparable across the rich world (see chart, left panel), though rigid minimum-wage laws in western Europe make it a bit of an outlier. Among emerging economies, wages vary from 32% of the American level in Russia to about 6% in India, enormous gaps for functionally identical work.

將麥工資轉換為一種通行貨幣生成了一張出奇漂亮的圖表，可以展現(xiàn)對于簡單而明確的任務所需勞動力成本的國際差異。在富裕國家之間，麥工資大致相若（見左側面板圖表），盡管西歐嚴格的最低工資法使得西歐的麥工資有點像離群值。在新興經(jīng)濟體中，工資從占美國水平32%的俄羅斯到占美國水平6%的印度不等，對于功能相同的工作也有巨大的差異。

Dividing the McWage by the local price of a Big Mac gives what the authors call Big Macs per hour (or BMPH). This statistic represents an alternative, PPP-like calculation of the real wage, taking account of the local cost of goods. Labour costs represent more than half the price of a Big Mac.

將麥工資除以當?shù)氐木逕o霸價格得到的就是底稿作者所謂的每小時巨無霸數(shù)（英文縮寫B(tài)MPH）。該數(shù)據(jù)代表了一項可選的、考慮當?shù)厣唐烦杀尽㈩愃瀑徺I力平價的實際工資計算方法。勞動力成本代表了過半的巨無霸價格構成。

Workers in less productive economies earn lower wages, but their Big Macs cost less to produce. The gap in worker welfare between rich and poor countries is therefore smaller than exchange rates suggest. In China, for instance, the exchange-rate-adjusted McWage is 11% of that in America. The BMPH real wage shows a much smaller gap. BMPH also erases the seeming advantage conferred on workers by western Europe’s minimum wages.

在生產(chǎn)率較低的經(jīng)濟體中，工人們掙的工資較低，但他們的巨無霸的生產(chǎn)成本也較低。因此富國窮國之間的工人福利差距比市場匯率所示的要小。比如在中國，按市場匯率校準的麥工資是美國的11%，但每小時巨無霸數(shù)所示的實際工資差距要小得多。每小時巨無霸數(shù)同樣也會消除由西歐最低工資給當?shù)毓と藗儙淼谋砻嫔系膬?yōu)勢。

Both versions of the real wage show large gaps in pay for similar work across economies. These are due, the authors reckon, to variation in “total factor productivity” (TFP) or the efficiency with which an economy transforms raw inputs into final goods. An estimate of TFP derived from their McWage analysis closely matches economists’ estimates by more traditional means.

兩種版本的實際工資都顯示了在不同經(jīng)濟體間對相似工作較大的薪酬差距。作者認為這些差距是因為“全要素生產(chǎn)率”（TFP）的不同或一個經(jīng)濟體將原料轉換為最終商品效率的不同。從麥工資分析中提取的對全生產(chǎn)要素的估計十分接近經(jīng)濟學家利用傳統(tǒng)方法所做的估計。

A quick look at fast-food wages can shed light on the globe’s vast gulfs in productivity and welfare. Those gaps are shrinking, and not simply as a result of rapid emerging-market growth.

對快餐工資的快速瀏覽可以揭示出全球在生產(chǎn)率和福利水平上的巨大差距。這些差距在逐漸縮短，縮短的差距并不僅僅是新興市場快速增長的結果。

Between 2000 and 2007 America’s McWage rose by 13% while the Big Mac price jumped by 21%, resulting in a net tumble in the BMPH real wage of 7% (see chart, right panel). Meanwhile, the BRICs advanced as McWages grew faster than Big Mac prices. The BMPH jumped by 53% in India, 60% in China and 152% in a Russian economy recovering from financial crisis in 1998. The going has been slower since then. Russia and China managed gains from 2007 to 2011. Most others did not, as food prices rose faster than McWages. Data gathered this summer for the 2012 calculations may show a further slowdown. Bad news for an emerging world still hungry for better living standards.

從2000到2007年，美國的麥工資上漲了13%，而巨無霸的價格卻上漲了21%，導致每小時巨無霸數(shù)所示的實際工資凈跌了7%（見右面板圖表）。同期金磚四國因麥工資上漲高于巨無霸的價格上漲所以實際工資得以增加。從98年金融危機中逐步復蘇之后，印度的每小時巨無霸數(shù)上漲了53%，中國上漲了60%，俄羅斯上漲了152%。自此以后的增長都較為緩慢。從2007到2011年，俄羅斯和中國成功實現(xiàn)了增長。其他國家大多數(shù)則因食物價格上漲快于工資上漲而并未實現(xiàn)增長。今夏為2012年的估算所采集的數(shù)據(jù)可能會顯示出進一步增速放緩。這對一個渴望更高生活水平的新興世界無疑是一個壞消息。

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注釋：

◎Working paper 工作底稿(working paper) 亦稱“工作底表”。將一定期間計算所得的資料或調(diào)查搜集得到的資料匯集一起，為取得一定數(shù)據(jù)而進行調(diào)整、試算、分析的一種表式。

關于Burger&Sandwich

◎Hamburger，或簡稱Burger，真正指稱的不是面包夾內(nèi)容物，而是那塊圓形的肉餅，所以一塊圓形的油炸碎肉餅（wikipedia原文：a cooked patty of ground meat ）無論是裝盤配菜（此用法在英國常見），還是夾面包（bun），都叫做Hamburger。它的詞源來自于德國城市漢堡，原意是指一種Hamburg steak，漢堡風格的牛排。

◎Sandwich，指的是面包和配菜/肉一起吃，（所以Hamburger如果指肉餅夾面包，是Sandwich的一種）。最常見的是兩片或更多片面包夾著內(nèi)容物，但是單片面包上面放著菜/肉的也算作一種Sandwich，叫做open sandwich；而現(xiàn)在流行的餅卷菜/肉也是一種sandwich。

文章中統(tǒng)一按字面翻譯。不作其他處理。

◎Purchasing power parity 購買力平價法 其研究的基本思路就是通過價格調(diào)查，測算不同國家貨幣購買力之間的真實比率，從而取代匯率，把某項經(jīng)濟指標轉換成以某一基準貨幣或國際貨幣為基礎的指標。

◎Total Factor Productivity 全要素生產(chǎn)率 又稱為“索羅余值”，最早是由美國經(jīng)濟學家羅伯特.索羅（Robert M.Solow）提出，是衡量單位總投入的總產(chǎn)量的生產(chǎn)率指標。即總產(chǎn)量與全部要素投入量之比。全要素生產(chǎn)率的增長率常常被視為科技進步的指標。全要素生產(chǎn)率的來源包括技術進步、組織創(chuàng)新、專業(yè)化和生產(chǎn)創(chuàng)新等。產(chǎn)出增長率超出要素投入增長率的部分為全要素生產(chǎn)率（TFP，也稱總和要素生產(chǎn)率）增長率。

◎The law of one price 一價定律，即絕對購買力平價理論，簡單的表述為：當貿(mào)易開放且交易費用為零時，同樣的貨物無論在何地銷售，其價格都相同。這揭示了國內(nèi)商品價格和匯率之間的一個基本聯(lián)系。

◎Back-of-the-napkin 字面義為餐巾紙的背后，引申為以簡明直觀的形式演繹深奧的理論。拉弗曲線最初就是阿瑟·拉弗為兜售自己的觀點而在餐桌上用餐巾紙為福特總統(tǒng)助手切尼所畫的一條繚草的曲線。