Fallacy of the political commentator

American voters respond to the state of the economy. When unemployment is going down, support for the incumbent president increases. When unemployment increases, voters move towards the opposition.  There seems to be consensus about this fact, which is largely true for several other countries.

Now the way to measure unemployment is through the report on jobs which is published monthly. So far so good.

From this the professional commentators seem to have concluded that voters will change their opinion on a given date of the month, with basis on the fall of the jobless rate. The enormity of this fallacy is unbelievable. Homework: identify the Latin name of this erroneous mode of reasoning.