According to the passage, one factor that causes unemployment and earnings figures to overpredict the amount of economic hardship is the

recurrence of periods of unemployment for a group of low-wage workers

possibility that earnings may be received from more than one job per workers.

Fact that unemployment counts do not include those who work for low wages and remain poor

Establishment of system of record-keeping that makes it possible to compile poverty statistics

Prevalence, among low-wage workers and the unemployed, of members of families in which other are employed