Warmest by how much, now?

NASA reports that September, 2016 is the new hotness, beating out September, 2014 by 0.004 degrees Celsius.

So, exactly how many different measurements taken with different equipment at different times and places do you have to combine to compute the world’s average temperature to 1/250th of a degree, which by my calculations is approximately the amount of hot air expelled by the opening sentence of a presidential debate?

If they hadn’t already convinced me that they’re just blowing (cool, dry) smoke up our asses, this would do it.