Why is the debt increasing more than deficit spending?

 One of the assumptions that I make in trying to predict the future debt level is that the debt will increase each year by the deficit for that year - it seems only logical.  But in fact the debt is increasing more than is needed to cover the deficit.  Let's look at the last 2 fiscal years.

In fiscal year 2022 (ending 9/30/22), the official deficit was $1.375 trillion.  However, this includes student debt relief of $379 billion that was struck down by the Supreme Court.  So the actual deficit was right at $1 trillion.  

Now compare this to the amount on the nation's credit card.  On 9/30/21 the debt to the public was $22.283 trillion.  On 9/30/22, this was $24.299 trillion, which is an increase of $2.016 trillion. What was the extra $1 trillion for?

Oh, you say, look at the balance in the checking account at the Fed.  On 9/30/21, the balance in the checking account was $215 billion.  The same account on 9/30/22 had $636 billion in it. So yes the balance did increase about $400 billion, but that doesn't explain the other $600 billion.

Now look at fiscal year 2023, which ended 9/30/23.  The official deficit was $1.69 trillion but you have to add in the student debt relief of $333 billion, to get an adjusted actual of right at $2 trillion for 2023.  The debt to the public on 9/30/23 was $26.33 trillion, which is right at $2 trillion more than 1 year earlier.  So this almost matches.  And the Treasury checking account at the Fed had $679 billion in it, which increased slightly from the previous year.  

So there is an anomaly with the FY 2022 data.

What about going forward?  As I already pointed out, in FY 2024 the Fed is on track to issue more than $3 trillion of new debt in excess of that needed to repay the existing debt, and this is $1 trillion more than is needed for the deficit.

Is this an ongoing problem, where the debt goes up $500 billion to $1 trillion more each year than the deficit?  Is so, what will this do to the debt projections?

To dramaticize this, I think a marketable debt total of $40 trillion is a significant event.  When will this occur?  According to the CBO projections, this should happen sometime in 2030. But if the debt goes up $1 trillion more than the deficit each year, I think the $40 trillion level could happen earlier, maybe 2028. 

It feels like something has change regarding the debt trajectory, and that we are facing a $2 trillion plus deficit in 2023 and $3 trillion plus in 2024 and later.  Hopefully this is not the case, but it seems like things are spiraling out of control ahead of schedule.