Here’s the nifty PLOS ONE chart that shows the literary misery index (red circles) versus the economic misery index (white circles).

We used to just track our misery by adding the unemployment rate to the inflation rate (it’s called the misery index), but some academics in Bristol and London just developed a system to determine our unhappiness based on literature. In a sad, sad paper published last week analyzing the frequency of miserable-sounding words in 5 million English language books, these academics found they were able to track general moods in the U.S. and UK successfully.

That’s right. There’s not just a misery index. There’s now a literary misery index. A new, bookish tool to measure our personal torment.

For the sake of this study, there were six categories of mood: anger, disgust, fear, joy, sadness, surprise. Alison Flood of The Guardian reports the “sadness” category included words like “repent,” “regret,” and “rue” as well as “depress,” “dismay,” and “dispirit.” The books employed in the study were archived in Google Books.

When are we most miserable, according to literature? Ten to eleven years after an economic downturn. In fact, literature proved to have a stronger correlation to the misery index than either one of the other determining factors, unemployment or inflation, taken on its own.

“It looked like Western economic history, but just shifted forward by a decade,” said professor Alex Bentley, lead author of the study and an anthropologist University of Bristol.

“Economic misery coincides with WW1 (1918), the aftermath of the Great Depression (1935) and the energy crisis (1975). But in each case, the literary response lags by about a decade, such that authors are averaging experiences over that decade,” explained co-author of the study Dr. Alberto Acerbi.

Is it taking authors ten years to finish writing these soul-crushing books? Sure, that’s a possibility. Bentley believes this lag may reflect the gap between sad, sad childhoods and the unique misery of early adulthood, when many terrible memories are formed, and that the people experiencing this unbearable misery can’t bring themselves to write about it until later.

The researchers ran the same analyses on 650,000 books in Germany to make sure they were onto something. “We were still very cautious about spurious correlations at this point,” said Paul Ormerod, an economist in London, “but then we found virtually the same results for German economic vs. literary misery.

“The results suggest quite clearly that, contrary to post-modern literary theory, literature serves a purpose. It informs people about the human condition, and the content adapts to the conditions of the time.”

And that human condition is miserable. If you want to get a sense of the books you’re reading right now, take a quick look at the U.S. Misery index around 2004. (Blue and red stand for unemployment and inflation in the bar graph.)

Looks bright and sunny compared to the wretchedness that will make its way into print in 2018, doesn’t it? And we’re staring down the barrel of 2021. Imagine all of the horrible things literature has in store for you.

Here’s an easy way to calculate your own literary misery index: the book you are reading right now x 10 years = way, way worse.