One month ago, when we last looked at the Fed's update of Treasuries held in custody, we noted something troubling: the number had dropped sharply, declining by over $22 billion in one week, one of the the biggest weekly declines since January 2015, pushing the total amount of custodial paper to $2.805 trillion, the lowest since 2012. One month later, we refresh this chart and find that in last week's update, foreign central banks continued their relentless liquidation of US paper held in the Fed's custody account, which tumbled by another $14 billion over the course of a week, pushing the total amount of custodial paper to $2.788 trillion, a new post-2012 low.



Today, to corroborate the disturbing weekly slide in the Fed's custody data, we also got the latest monthly Treasury International Capital data for the month of September, which showed that the troubling trend presented one month ago, has accelerated to an unprecedented degree.

Recall that a month ago, we reported that in the latest 12 months we have observed a not so stealthy, actually make that a massive $343 billion in Treasury selling by foreign central banks in the period July 2015- August 2016, something unprecedented in size.

Fast forward to today when in the latest monthly update for the month of September, we find that what until a month ago was "merely" a record $346.4 billion in offshore central bank sales in the LTM period ending August 31 has - one month later - risen to a new all time high $374.7 billion, or well over a third of a trillion in Treasuries sold in the past 12 months.



Among the biggest sellers - on a market-price basis - not surprisingly was China, which in August "sold" $28 billion in US paper (the actual underlying number while different, as this particular series is adjusted for Mark to Market variations, will be similar), bringing its total to $1.157 trillion, the lowest amount of US paper held by Beijing since 2012.



It wasn't just China: Saudi Arabia also continued to sell its TSY holdings, and in August its stated holdings (which again have to be adjusted for MTM), dropped from $93Bn to $89Bn, the lowest since the summer of 2014. This was the 8th consecutive month of Treasury sales by the Kingdom, which held $124 billion in TSYs in January, and has since sold nearly 30% of its US paper holdings.



As we pointed out one month ago, what is becoming increasingly obvious is that both foreign central banks, sovereign wealth funds, reserve managers, and virtually every other official institution in possession of US paper, is liquidating their holdings at a very troubling pace, something which in light of the action in the past week appears to have been a prudent move.

In some cases, like China, this is to offset devaluation pressure; in others such as Saudi Arabia, it is to provide the funds needed to offset the collapse of the petrodollar, and to backstop the country's soaring budget deficit. In all cases, it may suggest concerns about a spike in future debt issuance by the US, especially now under the pro-fiscal stimulus Trump administration.

So who are they selling to? The answer, at least until last month, was private demand, in other words just like in the stock market the retail investor is the final bagholder, so when it comes to US Treasuries, "private investors" both foreign and domestic are soaking up hundreds of billions in central bank holdings. As we said last month when we observed this great rotation in Treasuries out of official holders into private hands, "we wonder if they would [keep buying] knowing who is selling to them." Well, this month it changed, and after private investors had been happily snapping up bonds for 4 straight months, in September "other foreign investors" sold a whopping $31 billion, bringing the total outflow between public and private foreign holdings to $76.6 billion, the second highest number on record!

Meanwhile, while just three months ago yields had tumbled to near all time lows, suddenly the picture is inverted, and long-yields are surging on concerns that not only will the BOJ, the Fed, and maybe even the ECB will soon taper their purchases of the long end, but that Donald Trump is about to unleash a $1 trillion debt tsunami at a time when the Fed will not be available to monetize it.

While it is unclear under what conditions foreign buyers may come back, one thing is very clear: as of this moments the selling strike not only continues but is accelerating, and should the foreign liquidation of Treasuries fail to slow, Yellen will have no choice but to forget about hiking rates and focus on QE4 instead.