供需決定 Specialness 的高低：Specialness 與債券發行量、放空量以及借券市 4.
場的 。發行量低
Specialness；此外大量放空者也會引發較高 Specialness，如果指標債券供給量較 需求量大時，Specialness 會偏低，也甚至可能沒有 Specialness；一但有所謂 buy and hold Investors 買入主流券離開 RP 市場或借券市場時，Specialness 可能較高。
5. 冷門券進入角解無 Specialness：對發行已經很久的債券，也沒有在市場上交 易之
7. 交易商不借券時出現影子成本：交易商所持有指標債券出現 Specialness 時，
如果不借券出去，而是賣出短天 RP，則交易商會有所謂的影子成本。
而言，其 是不太願意將債券隨意借出，或是賣出較長天期 RP，最主要原因為，避免因
buy and hold Investors 買進債券，
如壽險業、大型銀行、基金，他們多半是擁有大量資金，很少拿出來調度資金，
將增加 Specialness：buy and hold Investors，
們多半是擁有大量資金者也很少進行放空；而放空多半是證券交易商，有些是
10. Buy and hold Investors 吸納籌碼 他
5.2 建議
相較於國內其他市場研究，公債市場的探討比較少見，然而近幾年來公債市 場新制度的建置，加上陸續將開發提供美債交易平台，代表此市場之重要性，然 而在各項商品進入茁壯與成熟的過程中，必須將相關可能或已經發生問題作整體 性考量，譬如是否應修改借券制度的利率上下限等等，以避免市場成交過於異常 之利率。以股市為例，融券放空股票時，僅在出現異常需要標借時，才會突顯標 借之異常，然而現行債券借券制度在出現負值後通常持續一段期間之異常利率，
更突顯台灣債市淺碟現象。
此外，作此研究探討時，發現台灣債券市場永遠活絡的只有指標券，也就是 只有主流 10 年券有交易，同時期的其他債券成交稀少，無法有效建立債市殖利 率曲線，且就指標債券而言仍欠缺完整資料，如持券行業別等資料，限制研究層 面的深度。
本資料僅實證在正常情況下，台灣債券市場借券利率也存在 Specialness，希 望這個研究能提供未來研究台灣債市之利率走勢，將 Specialness 或 Relative Repo Specialness 之利率或其持續期間及借券量成為重要指標變數，從中研擬出更 佳之交易策略模式。
本文於 2008 年 4 月份完成初稿後，仍觀注市場變化，2008 年債券市場因全 球農產品及油價飆升，嚴峻之通貨膨脹壓力引爆債券市場另一次空頭洗禮，然而 在過去不易出現於 Re-Open 後 Special Repo Rate 居然在 973 期 Re-Open 後，持 續出現負利率，檢視 973 總發行量為 750 億，可放空量為 375 億，在放空量不到 100 億上下，其 Special Repo Rate 最低可以低到 0.5%~-88%，顯示籌碼離開借券 市場及籌碼高度集中仍是左右 Special Repo Rate 的重要因素。
參考文獻
中文部分
〔1〕 林婉蓉，「債券市場效率化發展之研究」，證券櫃檯第104期~105期 p.48~73
〔2〕 周一誠，「美國公債交易實務—論其借券機制」證券櫃檯第132期 p.17~26
英文部分
〔1〕 Amihud, Yakov and Haim Mendelson,“Asset pricing and the bid-ask spread,”Journal of Financial Economics 17(2), 223–249, 1986.
〔2〕 Amihud, Yakov and Haim Mendelson,“Liquidity, Maturity, and the Yields on U.S.
Treasury Securities,” The Journal of Finance 46(4), 1411-1425, 1991
〔3〕 Bradford, Cornell and Alan Shapiro,“The Mispricing of U.S. Treasury Bonds: A Case Study,” The Review of Financial Studies 2(3), 1989
〔4〕 Buraschi, A and D Menini,“Liquidity Risk and Specialness,” Journal of Financial Economics 64, 243-284, 2001
〔5〕 Baba, Naohiko and Yasunari Inamura,“The Japanese Repo Market: Theory and Evidence,” Bank of Japan, Working Paper, 2002
〔6〕 Dufresne, Collin, Goldstein P R and Martin J.S,“The Determinantsof Credit Spread Changes,” Journal of Finance 56, 2177-2207, 2001
〔7〕 Duffie, Darrell,“Special Repo Rates,” Journal of Finance 51(2), 493-526, 1996
〔8〕 Federal Reserve Bank of New York, 1999, “Announcement of Revisions to the SOMASecurities Lending Program,” Posted at
www.newyorkfed.org/pihome/news/announce/1999/soma.html.
〔9〕 Fisher, Mark, “Special Repo Rates: An Introduction,” Federal Reserve Bank of Atlanta Economic Review 87(2), 27-43, 2002
〔10〕Fleming, Michael J,“Are Larger Treasury Issues More Liquid? Evidence from Bill Reopenings,” Journal of Money, Credit and Banking 34, 707-735, 2002
〔11〕Fleming, Michael J, and Kenneth D. Garbade. “When the Back Office Moved to the Front Burner: Settlement Fails in the Treasury Market after 9/11,” Federal Reserve Bank of New York Economic Policy Review 8(2) 35-57, 2002
〔12〕Fleming, Michael J,“Measuring Treasury Market Liquidity,” FRBNY Economic Policy Review 9, 83-108, 2003
〔13〕Fleming, Michael J, and Kenneth Garbade,“Repurchase Agreements with NegativeInterest Rates,” Federal Reserve Bank of New York Current Issues in Economics and Finance 10(5), 2004
〔14〕Griffiths, Mark D & Drew B Winters,“The Effect of Federal Reserve Accounting Rules on the Equilibrium Level of Overnight Repo Rates,” Journal of Business Finance & Accounting 815-832, 1997
〔15〕Goldreich, David, Bernd Hankea, and Pernendu Nath,“The Price of Future Liquidity:
Time-Varying Liquidity in the U.S. Treasury Market,” Centre for EconomicPolicy Research Discussion Paper 3900, 2003
〔16〕Goldreich, David, Bernd Hankea, and Pernendu Nath,“The price of future liquidity:
Time-varying liquidity in the u.s. treasury market,” Review of Finance 9(1), 1–32, 2005
〔17〕Graveline, Jeremy, M McBrady,“Who Makes On-The-Round Treasuries Special?,”
working paper, 2006
〔18〕Jegadeesh, Narasimhan,“Treasury auction bids and the salomon squeeze,” Journal of Finance 48(4) 1403-1419, 1993
〔19〕Jordan, Bradford D and Susan D Jordan,“Special Repo Rates: An Empirical Analysis,” Journal of Finance 52(5), 2051-72, 1997
〔20〕Keane, Frank,“Repo Rate Patterns for New Treasury Notes,” Federal Reserve Bank of New York Current Issues in Economics and Finance 2(10), 1996
〔21〕Krishnamurthy, Arvind,“The Bond/Old-Bond Spread,” Journal of Financial Economics 66, 463-506, 2002
〔22〕McCulloch, H J,“The Tax Adjusted Yield Curve,” Journal of Finance 30, 811-830, 1975
〔23〕Moulton, Pamela C,“Relative Repo Specialness in U.S. Treasuries,” Journal of Fixed Income 14(1), 40-7, 2004
〔24〕Sundaresan, S,“An Empirical Analysis of U.S. Treasury Auctions:Implications for Auction and Term Structure Theories,” The Journal of Fixed Income 35-50, 1994
〔25〕Shigemi, Y, S Kato, Y Soejima, and T Shimizu,“Market Participants' Behavior and Pricing Mechanisms in the JGB Markets: Analysis of Market Developments from the End of 1998 to 1999,” Bank of Japan Financial Markets Department, Working Paper, 01-E-1, 2001
〔26〕Subramanian, Darbha G K, “Commonality, predictability and pricing of liquidity in US Treasury Markets: An empirical analysis,” Working Paper, University of Chicago, 2005
〔27〕Vayanos, Dimitri,“Transaction costs and asset prices: A dynamic equilibrium model,”
Review of Financial Studies 1(1), 1–58, 1998
〔28〕Vayanos, Dimitri and Pierre-Olivier Weill, “A search-based theory of the on-the-run phenomenon,” Working Paper, 2005
〔29〕Warga, Arthur,“Bond Returns, Liquidity, and Missing Data,” The Journal of Financial and Quantitative Analysis 27(4), 605-617, 1992
附錄 台灣債券市場發行及交易發展進程