There's more to marital bliss than finding someone who texts back quickly.

We also want our partners to be loving, financially secure, and maybe have a college education (or two).

It wasn't always this way.

Before we had modern medicine and casual attitudes toward sex, people held far different opinions about what constituted a worthy spouse. According to a 2013 study, people in 1939 focused more on maturity, good health, and chastity compared to people in 2008.

The results of that study, which compared data across both time periods for 18 different traits, recently made its way to University of Oxford data visualization expert Max Roser, who runs the research website Our World In Data.

Here's the full breakdown, which Roser shared on Twitter:

OurWorldInData.org

Factors like emotional stability and religious background have held mostly steady. But certain traits stand out as stark reminders of the time each group lived in.

The 1939 respondents cared very little about their partner's political affiliation, education level, or financial status. More important was the quality of the person's character, whether they were dependable, neat, and well-suited for starting a family.

By 2008, those preferences were more or less turned on their head. People said they cared less about whether someone was a kind and reliable person and more about whether they matched their spouse's education level, political bent, and intelligence.

That kind of change squares well with all the data that finds younger generations are working longer hours than their parents and are more often sharing household duties in marriage.

Romance is becoming less about how people act, and more about how they think.