Well, yes, but it is even more mechanical than this.

Here is the simplified version:

Let's say I have a company worth 1 billion dollars, publicly traded, 10 million stocks worth $100 each. I get promised $100M from the state (aka taxpayers), shareholders estimate there is about 50% chance I will actually get the money: $100M * 50% / 10M = $5. It means the stocks are now worth $5 more, so $105.

Now the government has changed, and gone are my chances to get that money, so the sock is back to $100.