[Excerpt] This Congressional Budget Office (CBO) paper, which was prepared at the request of the Senate Committee on Finance, documents changes in the annual earnings of workers ages 25 to 54 between 1979 and 2007. CBO’s analysis compares the distribution of earnings for male and female workers and documents changes in the annual earnings of workers with very high earnings. The analysis also examines changes in earnings mobility (the rate at which workers move from one position in the distribution to another) and earnings variability (the extent to which a worker’s earnings change from one year to the next). In keeping with CBO’s mandate to provide objective, impartial analysis, this paper makes no recommendations.