译者 王为
文中黑字部分为原文，蓝字部分为译文，红字部分为译者注释或补充说明
Vanguard Long-Term Corporate Bond ETF: Likely To Remain Strong, But Concentration And Duration Risks Exist
by Zvi Bar
Summary
摘要
VCLT is a very long duration corporate bond fund.
VCLT是一只久期相当长的公司债基金
VCLT has increased considerably so far in 2019.
2019年至今VCLT的净值已大幅增长
VCLT could decline again if interest rates increase, and corporate credit quality issues are also a significant risk to VCLT.如果利率水平出现上升，VCLT的净值有可能会再次下跌，此外公司债的信用质量也是影响VCLT净值波动的重要因素
Limited prime and high-grade corporate paper are also developing into significant concentration risk.
优质高等级公司债的短缺也导致该基金的持仓集中度偏高
VCLT exposure is still a reasonable holding for income production and its potential for roll down returns, but only if accompanied with other holdings to reduce or hedge duration and interest rate risk.
从风险敞口的情况来看，VCLT仍能通过高票息和滚动收益带来不错的投资回报，但前提是削减投资组合内持仓的其他资产或对久期以及利率风险进行过有效地对冲
Vanguard's Long-Term Corporate Bond ETF (VCLT) is a passive portfolio of investment-grade corporate bonds and seeks to track the Bloomberg Barclays US 10+ Year Corporate Bond Index. VCLT represents the cheapest way to get broad exposure to the long-term investment-grade corporate bond market, but there are strong reasons why income investors should hedge their exposure to VCLT.
美国Vanguard基金公司发行的长期限公司债交易所交易基金VCLT是一只专门投资美国投资级公司债的被动投资组合，业绩参考指数为彭博巴克莱美国10年期以上期限公司债回报指数。VCLT是当前市场上成本最低的投资美国投资级公司债市场的金融工具，但强烈建议以现金流收益为目标的投资者应对冲VCLT基金所面临的风险。
VCLT's characteristics
VCLT基金的基本要素
Since VCLT is a portfolio of long-term bonds, the fund has significant exposure to interest rate changes. It obtains its 4.4% yield to maturity by having an average effective maturity of 23.8 years and an average duration of 13.5 years. Duration is an approximate measure of a bond's sensitivity to changes in interest rates.
(Source: Vanguard)
由于VCLT是一只长期债券投资组合，因此受利率波动的影响很大。该基金的到期收益率为4.4%，持仓债券的平均存续期限为23.8年，久期的均值为13.5年，久期是衡量债券价格受利率波动影响程度的敏感性指标，见下表。
As a result of this interest rate risk and the recent decline in interest rates, VCLT declined in 2018 and has appreciated considerably during 2019. VCLT is up about nine percent within the last five months but declined around 13% in the first 11 months of 2018. This volatility is due to VCLT's significant duration.
由于基金的净值受利率波动风险甚大，VCLT的净值在2018年出现下跌，但受近期利率水平下降的影响2019年以来净值经历了大幅增长。在过去5个月里，VCLT的净值上升了约9%，但在2018年的前11个月里下跌了13%左右，这一剧烈波动归因于VCLT的高久期特点。
With interest rates being so low again, there is a risk that they may correct and return to rising, but there is a near equal probability that they will continue to decline due to a slowing global economy. There are reasons why the US dollar denominated debt is likely to perform well in the current global economy, including both US Treasuries and corporate paper. Negative interest rates for sovereign paper with similar credit quality, such as Germany and Japan, and weakness across most emerging market currencies make US denominated paper from investment-grade sources attractive.
由于去年年底以来利率水平再次回到低位，因此未来的利率走势有可能逆转并重回上扬态势，但利率水平受全球经济减速的影响而继续下行的概率也旗鼓相当。有充分的理由认为，在当前的世界经济形势下，包括美国国债和美国公司债在内的美元标价债券，应能取得靓丽的回报表现。与美国国债信用度相当的德国和日本国债的回报率为负利率，再加上大多数新兴市场国家货币对美元汇率的走弱，导致投资级美元债券魅力日增。
VCLT's portfolio is made of almost 2000 holdings of various credit quality. VCLT endeavors to hold investment-grade bonds, but the spectrum of what is considered investment-grade is broad. VCLT presently primarily holds bonds in what is considered the upper medium and lower medium grades of investment-grade, as opposed to the higher tiers of prime and high grade.
VCLT的投资组合由大约2000只各类评级的公司债构成。按照投资范围的约定，该基金持仓应持仓投资级债券，但对于投资级债券的定义却相当宽泛。当前，VCLT持仓的主要是中高级和中低级别的投资级债券，而不是优质、高信用评级的债券，见下表。
(Source: Vanguard)
The above distribution by credit quality is not because the fund is seeking out lower quality bonds to juice the payout but rather largely because the investment-grade universe has become overwhelmed with medium-grade issuances. This has pushed VCLT's average credit quality to the BBB range, which is risky for a total portfolio.
上表为VCLT持仓债券的评级分布情况，该基金并非特意选择低评级的债券作为投资标的，而是在很大程度上因为投资级公司债市场中中等评级公司债的占比越来越高，从而导致VCLT持仓债券的评级均值处于BBB区间，抬高了整个投资组合的风险度。
VCLT is also concentrated by sector type and into certain issuers. VCLT is primarily composed of bonds from industrial, financial, and utility issuers. Much of VCLT's concentration is due to the underlying characteristics of the aggregate index, but the fund's advisor also generally selects a representative sample of securities to approximate the full target index in terms of key risk factors and other characteristics, such as duration, cash flow, quality, and callability.
VCLT还存在持仓债券发行人过于集中于某些行业以及某些特定发行人的问题。VCLT持仓债券的发行人主要集中于工业，金融和公用事业等行业板块，持仓集中度偏高的问题很大程度上是受到所跟踪债券指数自身特点的影响，但该基金的管理者通常也会挑选一些有代表性的公司债来体现整个指数的主要风险因素和其他一些特征，比如久期，现金流，评级水平和发行人是否可提前赎回等。
(Source: Vanguard)
Nonetheless, VCLT tries to keep sector and subsector exposure within tight boundaries relative to the target index. Because the fund does not hold all issues in its target index, some of the issues and issuers will be overweighted or underweighted compared to the target index.
不管怎样，VCLT还是致力于持仓债券发行人的所在行业尽可能与业绩参考指数的要求相一致。因为该基金并没有完全按照业绩参考指数的成分券构成来投资，因此一些持仓债券和发行人的集中度有可能高于或低于业绩参考指数的要求。
This concentration at the issuer level is starting to creep up as a risk: an issuer issue. These concentration problems are not easy to see because many of the largest issuers have multiple issues and the concentration will not necessarily pop up in a single issue. For example, if we look at the top holdings of VCLT, we see that Anheuser-Busch InBev (BUD) makes up holdings 1 and 6, and Verizon (VZ) makes up holdings 7, 9, 10, 11, and 13.
发行人集中度偏高的问题开始暴露出风险。这个问题不太引人注意，因很多大的公司债发行人发行了很多期债券，因此不太容易在某只债券上形成集中持仓的问题。以VCLT持仓额度最大的几只券为例，可以看到安海斯-布希啤酒公司所发的公司债占据了持仓额第一和第六的位置，威瑞森电信的公司债出现在第7, 9, 10, 11和13的位置上。
(Source: Vanguard)
There are actually 18 different Verizon bonds within the portfolio, maturities between 2029 and 2055, and these combine to be worth nearly as much as the listed top 5 holdings.
在VCLT的组合中实际上有18只威瑞森电信的各类公司债，到期日从2029年至2055年不等，金额加在一起几乎相当于VCLT持仓债券前五名的总和。
(Source: Vanguard)
There were also 18 Anheuser-Busch InBev issuances in VCLT when it last reported holdings and well over 20 AT&T bonds, but the total face value of Verizon bonds was greater (roughly 2.5% compared to 2%). Changes to the credit rating of such significant issuers could cause for more dramatic changes to the index in an effort to maintain average credit quality.
最新一期基金业绩报告显示，VCLT还持有18只安海斯-布希啤酒公司的公司债和20只AT&T的公司债，但威瑞森电信公司债的面值总额要高于前者，在基金中的持仓比例分别为约2.5%和2%。如果这些大公司的信用评级发生变动有可能导致业绩参考指数做出大幅调整以保持整个指数中成分债的平均评级水平不变。
VCLT's performance
VCLT的回报表现
VCLT declined about 13% in 2018 and has appreciated around 9% since the start of 2019. These are both significant moves for a portfolio of investment-grade bonds but rates have been volatile. This volatility could continue and in either direction.
VCLT的净值在2018年缩水了13%，而2019年以来则上涨了约9%，对于投资级债券来说这个波幅有点大。但由于利率水平大幅波动，因此基金净值大涨大跌的状况有可能持续下去，上下两个方向均有可能。
VCLT has moved like this before. It is actually becoming a somewhat recurring condition. See the ten-year chart below:
VCLT的净值以前也曾出现过类似的波动，因此当前的情况实际上是过去历史的重现，请见下面这张过去十年的净值走势图：
(Source: Yahoo! Finance; Arrows by Zvi Bar)
If we look at the five-year chart, we see that upon prior instances of strength to current levels, VCLT generally continued to appreciate. That is, where VCLT has previously appreciated to the low 90s, it tends to go to the mid 90s within the next few quarters.
再看看下面这张过去5年的净值走势图，以往如果出现当前的上涨势头，VCLT的净值通常会继续往上走。也就是说，如果净值升破90大关，通常会在未来几个季度里上行至95左右。
(Source: Yahoo! Finance; Bar by Zvi Bar)
This may indicate that VCLT's recent strength is likely to continue this time too. Further, it appears that continued strength may last for between two and four quarters.
VCLT基金近期的强劲表现有可能继续以往的走势。此外，从走势上看升势似乎应能持续2到4个季度。
There are strong reasons why long-term US dollar bonds may continue to perform well, including a growing demand for dollar income and concerns about global growth. Another often overlooked manner in which long-term bondholders can profit is through roll down return. Essentially, if interest rates remain depressed for an extended period of time, there is a strong potential for bonds to be sold at a premium as they roll down the yield curve. VCLT's portfolio cleans itself of paper as in falls from long-term into intermediate and those sales should result in appreciation in instances where interest rates have not substantially changed or have declined.
有充分的理由让人相信美元长期限债券为啥会表现靓丽，原因包括投资者对美元现金流的强烈需求以及市场对全球经济增长前景的担忧升级。另一个经常被人忽视的因素是，长期持仓债券的投资者可以通过滚动操作而获益。也就是说，如果利率水平继续在低位停留一段时间，随着持仓债券的到期日临近，投资者有可能以很高的溢价卖掉债券。如果VCLT将投资组合中存续期限已从长期变成中期的债券卖掉，就会产生很高的溢价收入，而利率水平却没有发生大的波动甚至还有可能下跌。
Conclusion
结论
VCLT offers investors cheap access to a broad index of long-term investment-grade bonds and a sizable income stream compared to comparable dated treasuries. VCLT has performed exceedingly well so far in 2019 due to declining interest rates and a strain US dollar. Prior instances of such strength were usually followed by continued strength into the mid 90s, and that history indicates this current appreciation may not be over.
VCLT给投资者提供了以较低的成本投资美国长期限投资级公司债市场的机会，与期限相近的美国国债相比，该基金的现金流收益更加可观。2019年初至今，在利率水平下跌和美元升值的影响下，VCLT的回报表现相当不错。在历史上，如果回报走势像当前这样强的话，净值通常会升至95左右，根据以往经验，当前的净值升势应尚未终结。
VCLT brings with it considerable duration risk and the investment-grade ratings have the potential of being inundated with downgrades due to leverage rates and other factors affecting individual businesses as well as global growth. VCLT's holdings are also in danger of becoming overly concentrated in issuances by major issuers within the investment-grade market. VCLT's duration risk may be mitigated by combining it with low duration income instruments or interest rate hedges.
VCLT本身也存在相当大的久期风险，持仓的投资级债券也有可能因各种因素被大规模降级，比如发行人财务杠杆率过高或全球经济增速放缓等因素导致特定发行人的业务受到负面影响。VCLT的持仓风险也有可能体现为过多地集中于投资级债券市场中某些主要发行人所发的债券上。但VCLT持仓的久期风险应可通过分散投资于低久期高票息债券或对冲利率风险等方式予以化解。