What does "measure" mean here?

[NewHopeR]

Context:
Throughout the Great Recession and the not-so-great recovery, the most commonly discussed measure of misery has been unemployment. But many middle-class and working-class people who are fortunate enough to have work are struggling as well, which is why Sherry Woods, a 59-year-old van driver from Atlanta, found herself standing in line at a jobs fair this month, with her résumé tucked inside a Bible.

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[emsr2d2]

In this context, it's means the method of measurement.

[a_vee]

They are looking at unemployment to measure the conditions. They are judging the situation by the amount of unemployment.