How is underemployment calculated?
I believe "underemployment" is also known as the "U6" unemployment rate. In addition to the traditional "U3" unemployed, it includes "marginally attached workers and those working part-time for economic reasons." Part-time work could be as little as 1 hour per week. The U6 is currently 14.9%.
And here some information on those who have dropped out of the labor force. When Barack Obama took office, the size of the U.S. labor force as a percentage of population was 65.7%. Today, it has shrunk to 63.9%. This represents both people dropping out of the workforce because they have given up looking for work, and also includes a natural attrition due to baby boomer retirement.
According to this guy, if you adjust for the shrinking of the workforce (
also taking into account natural baby boomer retirement), the unemployment rate would be
10.4%. So, this would indicate that the unemployment rate is being significantly reduced by people giving up looking for work. That seems ironic.