中級(jí)宏觀經(jīng)濟(jì)學(xué)講義9

IntermediateMacroeconomics91TheOpenEconomyWhydocountriestradewitheachother?“Nonationwaseverruinedbytrade.”---BenjaminFranklinMorevarieties;higherquality;cheaperprice2TheOpenEconomyMerchandisetradeasa%ofGDP(2005)

MerchandiseTrade(%ofGDP)Highincome43.6Uppermiddleincome66.7Middleincome62.2Lowermiddleincome58.8Lowincome41.13TheOpenEconomy

ArgentinaChinaEthiopiaFranceGermanyHongKongIndiaMexicoU.KU.S.MerchandiseTrade(%ofGDP)37.563.844.945.362.7333.728.25840.121.24TheOpenEconomyTheinternationalflowsofcapital&goodsFactorsaffectingCA(savingsandinvestment)ExchangeratesFactorsaffectingex-rate5InternationalFlowsofK&GoodsCapitalaccount¤taccount6InternationalFlowsofK&Goods(I-S)+NX=0 or KA+CA=0NX≡TB=CA(S-I)≡NFI=-KA7InternationalFlowsofK&GoodsS–I=NX(-KA=CA)IfS–I>0(KA<0)境內(nèi)儲(chǔ)蓄多于境內(nèi)投資部分儲(chǔ)蓄投資到國(guó)外(資本凈流出)外國(guó)人用這部分資金購(gòu)買(mǎi)我國(guó)商品(商品凈流出)NX>0;TB>0;CA>0;KA<08InternationalFlowsofK&Goods經(jīng)常項(xiàng)目順差：既定時(shí)期，一國(guó)居民向外國(guó)居民的貸出大于借入，從而對(duì)外凈資產(chǎn)增加。：本國(guó)的凈對(duì)外資產(chǎn)余額因此，t時(shí)點(diǎn)一國(guó)凈對(duì)外資產(chǎn)余額是過(guò)去經(jīng)常項(xiàng)目盈余或赤字的結(jié)果。

9投資于本國(guó)：I或凈對(duì)外投資：InternationalFlowsofK&Goods10InternationalFlowsofK&GoodsNX=CA=-KA?我們借來(lái)的錢(qián)是否可以全被用于購(gòu)買(mǎi)別國(guó)的商品服務(wù)?外國(guó)人借的人民幣是否可全被用于購(gòu)買(mǎi)我國(guó)的商品服務(wù)?No！Wepay/earninterestif(S–I)<>011InternationalFlowsofK&Goods通常情況下,相對(duì)于貿(mào)易余額,國(guó)外的凈要素支付很小。因此,經(jīng)常項(xiàng)目余額和貿(mào)易余額幾乎相等。Mankiw的假設(shè)CA=TB=-KA正是基于此12InternationalFlowsofK&Goods經(jīng)常項(xiàng)目包括：貿(mào)易余額利息/股息其他商品勞務(wù)和收入（旅游，工人匯款…）單邊轉(zhuǎn)讓官方轉(zhuǎn)讓其他13InternationalFlowsofK&Goods經(jīng)常項(xiàng)目余額部分構(gòu)成（2005年）（億美元）中國(guó)美國(guó)日本巴西商品貿(mào)易590-6，6201，321337服務(wù)貿(mào)易-97450-379-48要素收入-36-241857-205數(shù)據(jù)來(lái)源：IMF2006報(bào)告14InternationalFlowsofK&Goods2005ChinaCA:USD160.8billion數(shù)據(jù)來(lái)源：中國(guó)外匯管理局15InternationalFlowsofK&Goods項(xiàng)

目差額一.經(jīng)常項(xiàng)目1608.183

A.貨物和服務(wù)1247.977

a.貨物1341.891

b.服務(wù)-93.9139

B.收益106.3514

1.職工報(bào)酬15.19648

2.投資收益91.15491

C.經(jīng)常轉(zhuǎn)移253.8547

1.各級(jí)政府-1.76234

2.其它部門(mén)255.61716InternationalFlowsofK&Goods項(xiàng)

目差額

b.服務(wù)-93.9139

1.運(yùn)輸-130.21

2.旅游75.3693

3.通訊服務(wù)-1.18173

4.建筑服務(wù)9.73567

5.保險(xiǎn)服務(wù)-66.5014

6.金融服務(wù)-0.14244

7.計(jì)算機(jī)和信息服務(wù)2.17676

8.專有權(quán)利使用費(fèi)和特許費(fèi)-51.6385

9.咨詢-8.61408

10.廣告、宣傳3.60521

11.電影、音像-0.20096

12.其它商業(yè)服務(wù)74.97029

13.別處未提及的政府服務(wù)-1.2817517OtherInterpretations如何評(píng)價(jià)CA>0(S–I>0)？是好是壞？(S–I)>0國(guó)外比國(guó)內(nèi)更好的投資機(jī)會(huì)？量入為出的自律？18兩期國(guó)家跨時(shí)預(yù)算約束

C1>Q1TB赤字C1<Q1TB盈余

無(wú)投資。僅選擇消費(fèi)或儲(chǔ)蓄

19兩期國(guó)家跨時(shí)預(yù)算約束第一期消費(fèi)大于產(chǎn)出則第二期消費(fèi)必小于產(chǎn)出若第一期貿(mào)易逆差,則第二期的貿(mào)易必為順差

20兩期國(guó)家跨時(shí)預(yù)算約束

貿(mào)易逆差或經(jīng)常項(xiàng)目逆差本身并不說(shuō)明好壞，只是一國(guó)跨時(shí)選擇的結(jié)果?，F(xiàn)在逆差將來(lái)必須實(shí)現(xiàn)順差，現(xiàn)在順差將來(lái)必然享受逆差。21多期國(guó)家跨時(shí)預(yù)算約束

若為有限期，預(yù)算約束可得出與兩期模型相同結(jié)論：如果有些時(shí)期出現(xiàn)貿(mào)易（經(jīng)常項(xiàng)目）順差，必然有另外的時(shí)期是貿(mào)易（經(jīng)常項(xiàng)目）逆差。22但是，對(duì)于每個(gè)國(guó)家，時(shí)限可以被假設(shè)是無(wú)窮的，如何約束？可不可能永遠(yuǎn)是逆差或者順差？甚至借新債還舊債無(wú)限舉債（PonziScheme）？多期國(guó)家跨時(shí)預(yù)算約束23多期國(guó)家跨時(shí)預(yù)算約束美國(guó)會(huì)不會(huì)是Ponzi？2004：CA赤字0.67萬(wàn)億占GDP11.67萬(wàn)億的 5.7%2005：CA赤字0.79萬(wàn)億占GDP12.5萬(wàn)億的 6.3%2006：CA赤字0.85萬(wàn)億占GDP14.98萬(wàn)億的 5.7%美國(guó)的凈外債約占GDP的25％即使CA赤字穩(wěn)定在GDP的5％，2020年凈外債也會(huì)>GDP的60％24FactorsaffectingCA

---SmallOpenEconomyWhatmakesacountry“small”?---thescaleoftheeconomyissosmallthatitcannotaffecttheworldpricelevelPricetaker---takeworldrealinterestrate25FactorsaffectingCA

---SmallOpenEconomyr=r*Domestic&foreignbondsareperfectsubstitutesCapitalisperfectlymobile26FactorsaffectingCA

---SmallOpenEconomyModel27FactorsaffectingCA

---SmallOpenEconomyWorldreali-rateandCAKA=-CA=I–Srr*S,ICAISCA(r*)28FactorsaffectingCA

---SmallOpenEconomyI↑rtendsto↑$flowsintillr=r*NFI↓CA↓rS,IISEr*S=II’>S’=SCA=0CA<0

Shocktoinvestment(betterinfrastructure)29FactorsaffectingCA

---SmallOpenEconomyY↓S=(Y–C–G)↓rtendsto↑$flowsintillr=r*NFI↓CA↓rS,IISEr*Hurricane(temporaryshocktoproduction)S=I,CA=0S’<I’=ICA<030FactorsaffectingCA

---SmallOpenEconomyAsYconsistently↑,C↑Swouldnot↑asmuchAlso,investmentmay↑rS,IISEr*Technologicalimprovement(permanentshocktoproduction)temp.shock31FactorsaffectingCA

---SmallOpenEconomyTemporarytradesanctiononIraqTemporaryshocktoTermsofTrade(TOT)toChinaTOT↓Cwouldnot↓muchS↓rtendsto↑$flowsouttillr=r*NFI↓CA↓rS,IISES’<I’=ICA<032FactorsaffectingCA

---SmallOpenEconomyAlargeportionofoilfieldsinIraqweredestroyedduringthewaronTerrorismTOT↓permanentlypeoplewouldadjusttheirCSwouldnotdecreaseasmuch(orevengoesbacktoitsinitiallevel)CAdeficitmaydisappearfinally33FactorsaffectingCA

---SmallOpenEconomyFinancingfortemporaryshocks,adjustingforpersistent(permanent)shocks---IMFCompensatoryFinancingFacility(CFF)Acountrycouldaskforloanswhenitsincomefromexportsisinsufficientandtheinsufficientistemporary.34FactorsaffectingCA

---SmallOpenEconomyInfluenceofhomeexpansionaryfiscalpoliciesG↑orT↓S↓Iunchanged(S-I)↓NFI↓&NX↓(CA<0)rS,IISEI’<S’=SCA<035FactorsaffectingCA

---SmallOpenEconomyInaSOE,anexpansionaryfiscalpolicy(G↑orT↓)squeezesouttheNXHigherbudgetdeficitathomeleadstohighertradedeficit(currentaccountdeficit)---TheTwinDeficits36FactorsaffectingCA

---SmallOpenEconomyInfluenceofforeignfiscalpolicies(large)