I don't think the related link was researched properly...
They interviewed women aged between 20 and 65, 1950's women would now be aged in their 70's and would wholeheartedly agree that they had more sex back then than they do now!
Even if the researchers had 'gone back in time' and interviewed women in the 1950's they would have been coy about the number of times they had sex. These days we are more comfortable talking about our sex lives.
Sure, they had more time.... no television, few outside interests away from their homes, earlier nights to bed and less women with careers....
However, they didn't have contraception (ie the pill), and married couples had to bear the cost themselves for large families.
Single women were not given any financial support or free housing, like today.
If, as we are led to believe....Summers were longer and hotter, food tasted better, families were happier, neighbourhoods were friendlier, sweets were bigger, life was sweeter...etc ...
It follows that they were also getting more sex than now, as life was so perfect for them!
Frankly, I don't believe it!
Just another pop at us girls living in the 2000's!