I was specifically thinking of the Webb space telescope. Per Wikipedia, the budget estimates indeed laddered up in this way. [1] I would be mad at Congress if they decided to cancel it because of the next $1 billion cost increment.
Why would you be mad? In 2006 they had budgeted 4.5 billion and already spent 1 billion, cancelling it then would have let us spend 7bn+ on projects that weren't mismanaged.
[1] https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Cos...