Why a measure of the percentage of government positions still at work is not a true measure...
Of how the shutdown has altered the function of the state.
Let's put it this way:
Agency A, B and C are all massive and when put together constitute about a million individuals.
And all three of these agencies are advised by the relatively small Agency D which only has about 5000 employees.
Now, Agency D is entirely furloughed and one might be quick to say "Well, those 5000 employees only constitute a mere one half of one percent of all the employees in question."
Sure, but if Agency D is a crucial component of Agency A, B and C, we have effectively shuttered a million jobs in total. And then let's consider that Agency A, B and C cater, in one way or another, to about 100 million Americans and being effectively shuttered has all but completely halted this catering.
This is why the shut down is likely WORSE than is being advertised. And this is why the conservative meme "Not much is actually closed" is a pile of bullshit.