Treasury's bill share overshoots its advisers' ceiling by $800 billion

Treasury was set to retire more than $4 billion of 10- to 30-year paper starting September 9 and 10, 2026 ^[4], while average bill issuance has been running above $500 billion a week ^[7]. The support at the long end is eight tenths of one percent of one week of supply at the short end ^[1]. The ten-year went through 5 percent in mid-September anyway, its highest in 19 years ^[2]. Repo rates rose sharply over the same weeks, so the cheap end of the curve got more expensive too ^[11].

Crypto Briefing puts the bill share at nearly 22 percent of a debt stock above $40 trillion ^[5]. The Treasury Borrowing Advisory Committee, the market panel that advises on debt management, has long recommended 15 to 20 percent ^[6]. Two points above that ceiling is $800 billion of bills ^[3].

Roughly a third of outstanding public debt matures inside twelve months ^[8]. A third of $40 trillion is about $13.3 trillion ^[4], and one percentage point across that book is roughly $133 billion a year of extra interest ^[5]. Interest is already projected above $1 trillion in the current fiscal year, more than the US spends on defence ^[9]. A trillion on $40 trillion is an average rate of about 2.5 percent ^[6], which is what the unrefinanced stock still pays. At the ten-year's 5 percent, the same $40 trillion would cost $2 trillion a year ^[7].

The new buyer is a legal requirement. The GENIUS Act, enacted in July 2025, requires stablecoin issuers to back their tokens with 100 percent reserves held in T-bills maturing in 93 days or less ^[12]. Crypto Briefing says that mandate has made companies like Circle and Tether some of the most reliable buyers of short-dated government debt ^[13]. The publication cites analyst projections that a $2 trillion stablecoin market by 2028 would add $800 billion to $1 trillion of bill demand ^[14]. The top of that range is about 11 percent of the roughly $8.8 trillion of bills outstanding now ^[2][8], and about 7.5 percent of the $13 trillion that reprices every year ^[9].

On this evidence the twist has traded duration risk for reset risk and has not bought the long end. A $4 billion buyback was too small to hold it down. The counter-thesis is that the ten-year would sit higher without $1 trillion of bills absorbing the funding need ^[1], and that the $950 billion in the Treasury General Account ^[10] lets Secretary Scott Bessent wait out bad auction windows. At $500 billion a week, that buffer is 1.9 weeks of gross bill supply ^[10]. A ten-year back under 4.5 percent with the bill share still above 22 percent would settle it the other way. Crypto Briefing's own reading of the 5 percent yield is that "the bond market isn't entirely convinced" ^[17].