Any jobless person who has not looked for work in the past 4 weeks is not in the labor force according to the Bureau of Labor Statistics (BLS). Some of these jobless people who are not in the labor force indicate that they'd like to have a job and are available for work. The BLS classifies such people as marginally attached workers. Discouraged workers are marginally attached workers who give a job-market-related reason for giving up on their job search. Typically, discouraged workers give up on their search because they feel that there are no current opportunities for them in the labor market.

The unemployment rate is the number of unemployed persons divided by the labor force. The labor force is the sum of employed and unemployed workers; in this case, the labor force is (155,604,000+6,197,000)=161,801,000$\left(\mathrm{155,604,000}+\mathrm{6,197,000}\right)=\mathrm{161,801,000}$. Therefore, the unemployment rate is 6,197,000161,801,000×100%=3.83%$\frac{\mathrm{6,197,000}}{\mathrm{161,801,000}}\times \mathrm{100\%}=\mathrm{3.83\%}$.

The U-4 measure of labor underutilization adds discouraged workers to the ranks of the unemployed (and, thus, to the labor force):

If discouraged workers were included in the official unemployment rate, the reported unemployment rate would rise. Similarly, excluding discouraged workers from the official measure of unemployment may mask the true extent of underemployment in the economy.