The numbers: The U.S. ran a $100 billion deficit in October, the Treasury Department announced Tuesday.

That’s wider than the $63 billion deficit recorded in October 2017 as spending rose 18% while receipts increased by 7%. Adjusted for timing shifts, the deficit was nearly equal at $110 billion vs. $111 billion in October 2017, the Treasury said.

What happened: The U.S. spent $353 billion during the month while it only took in $253 billion.

The U.S. spent $84 billion on Social Security, $69 billion on defense, and $53 billion on Medicare.

The big picture: As October is the first month of the government’s fiscal year, it’s still very early to project whether the annual budget deficit will reach $1 trillion after ending fiscal 2018 at $782 billion.

The Congressional Budget Office projects the deficit will come in just shy of $1 trillion, at $981 billion, due to the impact from the Tax Cuts & Jobs Act and new spending. The deficit more generally is expected to widen as the baby boomers age — boosting entitlement spending while cutting revenue.