The biggest one in my mind is the unemployment rate. Even though Labor publishes nuanced statistics and revises them for accuracy, Trump and the media focus solely on the lowest tier of unemployment rate, which is the one below 4%.
To be included in this rate, you must currently be receiving unemployment benefits from the state. Additionally, you must not be working part time at all, such as someone who drives uber for a few hours a week, or someone who picks up minimum wage shifts as a cashier or waiter. Lastly, you must submit weekly reports (through an imho easy to use online portal) of where you applied for jobs. You also cannot be in university, or living abroad (except Canada).
These hurdles are enough to remove literal millions of people from the official unemployment stat vis a vis the workforce participation stat. And yet, the incessant focus on Unemployment Rate probably won't stop.