I assume the low rate from 1948-84 was due to 1 person working in a married household. Then it increased as both persons worked to maintain middle class, follo

I assume the low rate from 1948-84 was due to 1 person working in a married household. Then it increased as both persons worked to maintain middle class, followed by recession. So low labor participation with high prosperity back then, and low participation with low prosperity now.