前回エントリで紹介したブランシャールのツイートにGeorge Selgin が反応し、自分が以前(3月5日)書いた表題の記事(原題は「On Empty Purses and MMT Rhetoric」)にリンクしている。そこでは、「政府支出は自動的に貨幣創造によって賄われる」という趣旨のケルトンの主張に反論すると同時に、ブランシャールのいわゆる「FRB財務省口座残高をマイナスにはできない」という点について詳説している。

Professor Kelton insists, on the contrary, that Congress “is not like a household or even a business.” In the government's case, she suggests, the Fed will fill any breach "by creating new money." In other words, the government doesn’t have to worry about its checks ever bouncing, because the Fed will cover any shortfall.
But that just ain't so. Indeed, when it comes to being able to rely on its bank to cover its expenditures, Congress is in one crucial respect more constrained than ordinary households and businesses are. That’s because, although most bank depositors enjoy certain overdraft privileges, and the Fed once granted similar privileges to the Treasury, in 1981 Congress itself permanently eliminated the Treasury’s overdraft privileges. Consequently, if Congress is to avoid running out of money, it can’t write checks in amounts exceeding the balances in its TGA account.
Furthermore, as Eric Tymoigne, another well-known (and especially thoughtful) Modern Monetary Theorist, explained in a blog post written several years ago, even when the Treasury did enjoy overdraft privileges on its TGA account, it made only very limited use of them, and never did so “because it was running out of money.” In those days, and indeed until the 2008 crisis, besides its TGA (“Treasury General Account”) balance at the Fed, the Treasury also maintained substantial balances in TT&L (“Treasury Tax and Loan”) Service accounts at various commercial banks. Although the Treasury occasionally overdrew its TGA account, thereby borrowing a corresponding amount from the Fed, it never borrowed more than it had available in its TT&L account balances. Instead, it borrowed in anticipation of anticipated receipts to avoid making temporary withdrawals from those TT&L accounts that would otherwise have necessitated countervailing Fed open-market operations.
In short, while they were still permitted, the Treasury’s TGA overdrafts served, not to make life easier for Congress, but to make it easier for the Fed.


Might Professor Kelton's claims be at least partially vindicated by the existence of some mechanism through which Congressional disbursements that reduce the TGA balance automatically lead to corresponding, additional Fed security purchases? No such luck. It's true that, under the pre-2008 system, disbursements from the TGA account tended to be expansionary, because they shifted high-powered base dollars into the commercial banking system. Once there they tended to flow into the fed funds market, reducing the effective fed funds rate, on their way to ultimately promoting disproportional expansion in the quantity of bank lending and deposits. But for that very reason the Fed routinely resorted to open-market security sales to offset such shifts.
TGA残高を減らす議会の歳出はFRBによる相当額の追加的な国債購入に自動的につながる、という何らかの仕組みの存在によって、ケルトン教授の主張は少なくとも部分的には正当化され得るだろうか? 話はそう上手くは行かない。2008年以前の制度下でTGA口座からの歳出に拡張的な傾向があったのは事実だ。というのは、ハイパワードマネーを商業銀行システムに注入したからだ。そこからFF市場に流れ込み、実効FF金利を引き下げ、最終的には銀行の融資額と預金額の一方的な拡大を促した。しかしまさにそのために、FRBは、そうした変動を打ち消すべく定期的に公開市場で国債売却という手段を採った。


But while it’s true that, prior to the recent crisis and other things equal, transfers from the Treasury’s TT&L accounts to its TGA account (as opposed to disbursements from the TGA itself) called for offsetting Fed open-market bond purchases, such purchases add, not to the government's bank balances, but to the balances of bond dealers. To raise a like amount of revenue for itself, the government would have to sell a like amount of additional bonds. That is, it would have to raise extra money by going further into debt. Tymoigne’s claim that “the Treasury will get financed by the Fed because only the Fed supplies the funds that the Treasury uses” is a non-sequitur. The Treasury will get financed only if it either taxes or borrows more — though the Fed may assist it in doing the last of these by increasing its own purchases of Treasury securities.
In today's environment of abundant excess reserves, in contrast, it’s no longer necessary for the Fed to offset movements of high-powered money either into or out of the TGA, because such movements no longer translate into increased bank borrowing or lending on the fed funds market, and a corresponding tendency for the effective fed funds rate to differ from its assigned target.