At the moment the government's debt total stands at £1.6 trillion. Not a trifling amount.
In March, the Office for Budget Responsibility forecast it would rise to £1.74trn by 2021.
Many economists predict that another £100bn can be added to that because of the predicted slowdown in economic growth and weaker tax receipts.
That would take the government's net debt to £1.84trn.
On top of that comes a further £100bn that could be added to the debt figure to account for financial support for banks announced after the referendum by the Bank of England.
That extra £100bn comes after a ruling on accounting for the Bank's support by the Office for National Statistics.
That takes the debt figure to £1.94trn.
If any of those numbers are worse than expected when Philip Hammond delivers the Autumn Statement then the overall debt figure could start flirting with £2 trillion.
Which is not a very comfortable headline.
There is a reason why the Treasury knows that today's government debt figures will not make for pretty reading.