How Have the Faces Changed?

I found this interesting. An archive has been created of the more than 300,000 faces that have appeared in Time magazine from 1923 to 2014. From the analysis:

Our first investigation looked at the relationship between the representation of women in the magazine, and cultural attitudes towards women. Focusing on the period between the 1940s and the 1990s, we found that the percentage of women’s faces found in Time between the 1940s and 1990s correlates with attitudes towards women in both the larger historical context as well as within the textual content of the magazine.

and

An interesting pattern emerges in the smoothed data, notably an increase in the proportion of female faces from the 1920s to 1945, a post-Second World War dip, a rebound beginning in the mid-1960s, followed by a decrease in the 1980’s, and a final rebound beginning in the early-1990s.

We found that this trend was very consistent with the attitudes towards women expressed in the text of the magazine, and also with larger historical trends. Women increased their participation in public life as they entered the workforce during the Second World War, were ushered out of public life during the post-war period until the women’s liberation movement of the 1970s. In the 1980s, we saw a backlash against feminism and a return to feminism starting in the early 1990s. These trends in cultural attitudes toward women tend to track well with the extent of their representation in the news magazine.

A lot of the women are smiling since so many of the faces appear in advertisements and advertisements are more likely to depict smiling people, presumably happy with their consumer behavior.