It gets closer to zero when i have problems focusing and so go into runaway internet time burning. This typically happens when some exciting/problem solving part of a project concludes, and i'm left with either a million possible ways to move forward past the solved problem, or a need to do the boring "awesome, now make it work" part of a project.

Procrastination is a problem solving decompression sickness.

It get closer to "code until a non maskable sleep interrupt fires" when there is a problem and the solution is close or something does not work but should, or something that haven't worked for a while finally starts to.

Between the two extremes there is pretty much any times depending on things to be done and free time available.