????尼古拉?斯萬知道他將不得不卷入發生在華盛頓的、圍繞美國負債攀升的辯論激流。

????作為標準普爾(Standard & Poor's)的分析師，斯萬一直留意可能危及美國作為一級借款人地位的事件。他注意到了美國向美國國際集團(AIG)、美國最大的幾家銀行以及按揭公司房利美(Fannie Mae)和房地美(Freddie Mac)注資數十億美元，研究了零利率和量化寬松政策對美國的影響。

????但直到今春的政治僵局令經濟建設性對話的希望成為泡影，斯萬才感到有一天美國可能會遇到還債問題。預算案導致美國聯邦政府差一點關門。不清楚美國國會是否會調高負債上限，以準確反映今年美國將支出多少。美國共和黨和民主黨提出的解決赤字方案迥異，雙方都不愿妥協。

????正如我們所知，周一斯萬發布了一份報告，稱標準普爾現給予美國前景負面，如果政客們不能找到協作方式，還可能下調美國的AAA信用評級(這是最高等信用評級)。報告立刻引發了熱議：美國能償還日益攀升的債務嗎？

????美國白宮和財政部都試圖淡化該評級，理由是評級過于關注政治因素，太主觀，意義不大。

????但政治完全有理由是主權評級中最重要的因素之一。國家不同于企業，國家可以制定影響其償債能力的法律法規。比如，通用汽車(GM)的債務和養老金負擔膨脹到公司靠賣車已無力償還時，公司只能申請破產。而美國能以償債的名義，增加稅賦，多印美元，改革福利計劃和權利。

????“標準普爾并不打算影響任何主權信用政策，但政治確實影響信用可靠度，”標準普爾主權信用分析師兼準則委員會成員瑪麗?卡瓦諾表示。

標準普爾如何進行主權評級

????像斯萬這樣的分析師通常研究五大領域，包括政治機構和趨勢、經濟和增長前景、政府收入狀況(包括一個國家如何獲得收入，用于何處以及有多少負債)、貨幣靈活性以及該國債券的市場流動性如何。

????和許多主權債務分析師一樣，斯萬是經濟學家出身。他曾就職于加拿大央行(Bank of Canada)以及加拿大聯邦政府財政部（Canadian Federal Government Department of Finance），并是百慕大和加拿大多個政府機構的主分析師。

????分析師們不僅盡可能地搜集各類信息，還與政府及央行官員進行至少每年一次的會面，卡瓦諾表示。這些所謂的管理層會面也可能包括公司主管——如果一國經濟倚重某個行業，如礦業或旅游業——和重要的經濟學家。

????本月斯萬與美國財政部和白宮經濟團隊成員進行了大量的交流，解釋為何他如此擔心華盛頓的政治僵局。斯萬認為解決赤字的方案要可信，必須要得到美國共和黨和民主黨的一致認同，他的擔憂是眼下政客們可能不合作。

????根據與官員的對話和研究結果，斯萬撰寫了一份報告，建議標準普爾給予美國負面前景。這意味著如果政客們無法就解決赤字達成一致，兩年內美國信用評級可能被調低。這不是最嚴重的下調警告(最嚴重的是負面關注，即60-90天內可能下調評級)，但對于一個自1941年標準統計公司（Standard Statistics）與普爾出版公司（Poor's Publishing）合并以來信用評級持續為最高AAA級的國家而言，這無疑是一個大舉動。

????在宣布下調前景前的一周，斯萬的報告被提交至一個約由六位信用分析師組成的委員會，經過了數小時的討論。“評級決定由來自不同大陸主權債務分析師組成的一個委員會做出，”卡瓦諾表示，“在主分析師做出簡短的口頭報告后，我們對五大領域進行了逐一審議。”標準普爾和穆迪(Moody's, 穆迪有類似的流程)的前分析師們將這個過程相比于學術辯論和交叉驗證。

????該委員會對斯萬的報告進行了投票，最終同意下調標準普爾的美國前景評級。視國家規則而定，標準普爾通常會在投票后數天內公布信用委員會的審議結果。據稱在標準普爾公布下調美國前景評級前，白宮曾試圖讓其改變主意，但太晚了。

????希望美國的政客們能利用標準普爾的報告契機，擱置兩黨斗爭，提出雙方都能認同的赤字削減方案。斯萬至少給了美國政府合理的警告。市場往往不會如此寬容。

????Nikola Swann knew that he would be thrust into the firestorm raging in Washington D.C. over America's growing debt burden.

????Swann is the analyst at Standard & Poor's who monitors the United States for events that could threaten the country's status as a top-tier borrower. From his perch in Toronto, Swann has watched the US inject billions of dollars into AIG (AIG), the nation's largest banks, and the mortgage companies Fannie Mae (FNMA) and Freddie Mac (FMCC). He has studied the effect that zero percent interest rates and quantitative easing have had on the country.

????But it wasn't until this spring's political gridlock destroyed any hope for productive conversations about the economy that Swann felt that US might someday struggle to pay its debts. The government had come close to shutting down over the budget. It was unclear whether Congress would raise the debt ceiling to accurately reflect what the country will spend this year. And Republicans and Democrats were unwilling to reconcile their vastly different plans to tackle the deficit.

????As we all know, Swann issued a report last Monday saying that S&P now has a negative outlook for the US, and could downgrade the country's top triple-A credit rating if politicians can't find a way to work together. The report sparked debate over whether America would be able to service its growing debt load.

????The White House and Treasury attempted to dismiss the outlook as too focused on politics, and therefore too subjective to have any meaning.

????But with good reason, politics is among the most important factors in sovereign ratings. Countries, unlike companies, can set the very laws that affect their ability to pay creditors. For example, GM's (GM) debts and pension obligations grew so large that the company simply could not sell enough cars to pay the tab. The company had to file for bankruptcy. The United States, on the other hand, can raise taxes, print money, and reform welfare programs and entitlements, all in the name of servicing debt.

????"S&P does not try to influence policy for any sovereign credit, but politics does influence creditworthiness," says Marie Cavanaugh, an S&P sovereign credit analyst and member of the company's criteria committee.

How S&P makes sovereign ratings

????Analysts like Swann study five broad areas, including political institutions and trends; the economy and its growth prospects; the revenue picture (including how a country can raise money, what it spends on, and how much debt it has); monetary flexibility; and how liquid the market is for that country's debt.

????Like many sovereign analysts, Swann is an economist by training. He has also worked at the Bank of Canada and the Canadian Federal Government Department of Finance, and he is the primary analyst for several government entities Bermuda and Canada.

????Analysts not only read all they can, they meet with government officials and central bankers at least once a year, says Cavanaugh. These so-called management meetings might also include heads of companies if the country is economically dependent on a single industry, like mining or tourism, as well as important economists.

????Swann spent much of this month talking to Treasury and members of the White House economics team to explain why he was so worried about DC's political gridlock. The only credible plan to deal with the deficit will be one that Democrats and Republicans can agree on, Swann believed, and he was worried that politicians right now aren't inclined to work together.

????Based on conversations and studies, Swann wrote a report recommending that S&P put the US on negative outlook, meaning that it could be downgraded in the next two years if politicians can't agree on a way to deal with the deficit. It wasn't the most severe downgrade warning (that would be negative watch, which means a downgrade within 60 to 90 days), but it was a big move for country that has been rated triple-A since 1941, when Standard Statistics merged with Poor's Publishing.

????In the week leading up to the downgrade, Swann's report was distributed to a team of about half a dozen other credit analysts, and then debated for hours. "Rating decisions are made by a committee that consists of sovereign analysts from different continents," says Cavanaugh. "After the primary analyst gives a short oral report, we go through the five categories." Former analysts at S&P and Moody's (MCO), which has a similar process, liken the procedure to a cross between and academic debate and a cross examination.

????The committee voted on Swann's report, and ultimately agreed to downgrade S&P's US outlook. Depending on country-specific rules, S&P generally announces credit committee results within days of the vote. The White House reportedly tried to get S&P to change its mind about downgrading the outlook for the US before it announced the downgrade, but it was just too late.

????Hopefully our politicians will use the S&P's report as cover to put aside bi-partisan fighting and come up with a deficit reduction plan they can agree on. Swann at least gave the government fair warning. Markets tend not to be so generous.