Democrats increase tax collection and increase expenditures, the net result is a lower deficit, mixed with some tricky accounting.
Republicans decrease tax collection (tax cuts) and decrease expenditures where they can, the net result is a higher deficit.
Why is this? It’s the effect of unfunded mandatory spending, where payments are established by existing laws going back as far as the 60s, piled on over time they can’t be cut. Some don’t change and some increase based on a formula established in the law.
