[pragmar]

It's not statistically incorrect. KPIs are generally discussed in time frames, year over year, quarter over quarter. There is year over year growth in multiple jobholders, three years running. That constitutes a strong trend, even if regressing to the mean. Also, if you're not filtering your multiple jobs data to prime age, you should use aggregate participation rate (unfiltered), which tells a different story.[0]

[0] https://fred.stlouisfed.org/series/CIVPART

[laidoffamazon]

It's prime age because our population pyramid is balanced towards people that are likely to retire about now anyway. The prime age is far more relevant.

And for the record, the year over year growth should indicate that it's not the negative economic signal OP implied it was, since the economy was otherwise weaker during the bottom of the metric!