What we found: As you might imagine, the real surge in literary novels with science fiction themes came in the past five or six years, after literary journal Conjunctions published its "New Wave Fabulist" issue and magical realism was on the wane. There were literary novels with SF themes, like David Foster Wallace's Infinite Jest, which didn't really fit into the general subject areas of "alternate history," "time warp," or "post-apocalyptic." We were most interested in seeing which years featured the most literary novels featuring those themes.

Of those three subcategories, alternate history was the most consistent, with literary authors using it to explore how wars could have gone differently, but also other topics. Not surprisingly, you saw more alternate history novels at the start of this period, when the U.S. was active in Somalia and still bombing Iraq, and then at the end, when we had invaded Iraq. Alternate history is traditionally a fairly conservative genre, with authors like Newt Gingrich dabbling in it and exploring how things could have turned out worse if we hadn't stiffened our spines. But a recent spate of alt-history novels is more liberal, exploring a world where the Aztecs never fell (Atomik Aztex) and a world where the Jews got a homeland in Alaska and we avoided the Middle East conflict (Yiddish Policemen's Union).

There was a boomlet in time-travel fiction, and stories about time acting strange, in 2003-2004, with Audrey Niffenegger's The Time Traveler's Wife proving a huge mainstream hit. This was the peak of the Bush-era resurgence in conservativism, with a lot of mainstream nostalgia about World War II and the Greatest Generation.

And then was a boom in post-apocalyptic fiction in more recent years, with three huge classics of the genre hitting in 2006. In particular, Cormac McCarthy's The Road has become the poster-child for the literary-authors-going-speculative trend. These books coincided with the Indian Ocean Tsunami, Hurricane Katrina, and a worsening Iraq conflict. But there's been a lull in the post-apocalyptic genre since then as well.

As you can see, Trek's crews have always treated the Prime Directive like a speed limit on the Interstate. But the high point of Prime Directive violations was the late 1990s, which surpassed even the late 1960s of Kirk's cowboy-ism.

At the same time, the United States was reducing its troop presence around the world. Why did Starfleet start interfering more, even as America was throwing less of its weight around? The late 1990s was an era of military spending cutbacks and base closures, when the U.S. seemed to be less influential without the threat of the Soviet Union to rally our own citizens, let alone our allies.

I know what you're going to say: It's all down to Star Trek: Voyager's Captain Janeway and her "anything goes" approach. But first of all, Janeway's not the only culprit. Ben Sisko on Deep Space Nine also played fast and loose with the Directive more in the late 1990s than in its earlier seasons. And the Federation also threw its non-interference principles out the window, in different ways, in both 1998's Star Trek: Insurrection and 2002's Star Trek: Nemesis.

But also, consider that Voyager is a metaphor for the U.S.' more confusing situation after the Cold War. Instead of being one superpower facing another (like the Klingons, Romulan or Borg) suddenly the Voyager is isolated in a quadrant full of independent players, each of whom has its own agenda. Just as the Soviets were replaced with Bosnians, Serbs and Kosovans and the U.S. had to form alliances to deal with messy situations, Voyager faces a bunch of warring races and Janeway has to strike deals with different races to escape in one piece.

All of which makes us wonder: If Star Trek were on the air as a television show now, and it took place during an era where the Directive applied, would we see fewer violations? After all, U.S. troop levels in other countries have rebounded, and we're once again involved in a massive confrontation overseas. Would a 24th century Trek step more lightly around the galaxy, to counterbalance the United States' greater use of force?

Illustration by Stephanie Fox. Additional reporting by Nivair H. Gabriel.

To some extent, it's understandable that space adventures play fast and loose with physics. After all, who wants to watch Han Solo spend years on the journey to Alderaan, only to find that the planet has twice Earth gravity and he can barely stand up, much less swagger?

The categories of mistakes in our report card should be pretty self-explanatory, but just in case, I'll expand on them a little bit:

• There's no sound in space
• Not all planets have Earth gravity
• Planets should have diverse climates, instead of one unified climate across a "desert planet" or "forest planet."
• It shouldn't be too easy to communicate with alien creatures, without some kind of high-technology "translator" explanation.
• And it definitely shouldn't be too easy for humans to interbreed with aliens.
• Humans exposed to vacuum without a spacesuit shouldn't explode or shatter. And a "hull breach" where the ship's crew is exposed to vacuum should kill everyone instantly.
• You can't have fires in space, unless there's oxygen leaking out somehow.
• Asteroids or other objects shouldn't be able to float close together without falling into each other's gravity
• People shouldn't be able to dodge lasers and other speed-of-light weapons
• And there's no reason why someone would move in slow-motion in zero gravity.
• Faster-than-light travel is probably not ever going to be possible.

The data is most striking for the period of 1995-1998, when the U.S. economy was at its bounciest. But there's also a nice spate of dystopian films in the mid- to late-1980s, when "morning in America was at its sunniest. There was also a spike in 2002-2006, during a fairly expansionary period.

So what's going on here? A few explanations suggest themselves. Movie execs may greenlight dystopian films during economic downturns, and their immediate aftermath, but it may take a few years for those films to work their way through the development process and hit your screens. But it's also possible that when things are at their brightest economically, people feel the most insecure because they know the good times won't last forever. So boom times are when people most need stories about people surviving the bad times. Or maybe it's just that film-makers are a contrary bunch, who want to rub your face in the dirt just when you're feeling your brightest.

Here's our list of dystopian films for each year. Feel free to let us know what we left out, or shouldn't have included:

2008
Cloverfield (D)

2007
I Am Legend (D)
28 Weeks Later (D)
Resident Evil: Extinction (D)

2006
V for Vendetta (D)
Idiocracy (D)
Children of Men (D)
Ultraviolet (D)

2005
Star Wars: Episode III - Revenge of the Sith (D)
Batman Begins (D)

2004
The Day After Tomorrow (D)
Stepford Wives (D)
Resident Evil: Apocalypse (D)

2003
The Matrix Reloaded (D)
The matrix Revelations (D)
Terminator 3: Rise of the Machines (D)

2002
Star Wars: Episode II - Attack of the Clones (D)
Minority Report (D)
28 Days Later (D)
Equilibrium (D)
Resident Evil (D)

2001
Planet of the Apes (D)
A.I. Artificial Intelligence (D)

2000
Battlefield Earth (D)

1999
The Matrix (D)
Existenz (D)

1998
Pi (D)
The Truman Show (D)
The X-Files (D)

1997
Alien: Resurrection (D)
Fifth Element (D)
The Postman (D)
Starship Troopers (D)
Gattaca (D)

1996
Escape from L.A. (D)

1995
Waterworld (D)
Mortal Kombat (D)
Johnny Mnemonic (D)
Judge Dredd (D)
Strange Days (D)
Twelve Monkeys (D)
Tank Girl (D)

1994
none

1993
Jurassic Park (D)
Demolition Man (D)
Robocop III (D)

1992
Batman Returns (D)
Alien 3 (D)
Freejack (D)

1991
Terminator 2: Judgment Day (D)

1990
Total Recall (D)
Handmaid's Tale (D)

1989
Batman (D)

1988
The live (D)

1987
Robocop (D)
The Running Man (D)

1986
Aliens (D)
The Fly (D)

1985
Brazil (D)
Mad Max: Beyond Thunderdome (D)

1984
The Terminator (D)

1983
none

1982
Blade Runner (D)
Videodrome (D)
Liquid Sky (D)

1981
Time Bandits (D)
Heartbeeps (D)

1980
The Empire Strikes Back (D)

1979
Alien (D)

1978
Invasion of the Body Snatchers (D)

Image by Stephanie Fox.

Methods: We compiled a complete list of cyberpunk novels and movies, by date, from a variety of sources including Wikipedia, the Cyberpunk Review, Amazon.com's cyberpunk lists and various other sites. Then we tallied the number of novels (red line) and movies (blue line) per year. We were hoping for a nice smooth curve, but it didn't happen. We're sorry the chart turned out so zig-zag, we were as surprised as anybody.

Results: Cyberpunk has gone in waves, judging from our data. Novels in the genre have had a few high points. The biggest peaks for novels were the late 80s (eight novels in 1988), and then the mid-90s (an average of 6 novels per year from 1993-1996). Cyberpunk films had a peak in the late 80s-early 90s, followed by a brief lull. There were ten cyberpunk movies each in 1993 and 1995, and then another lull. The genre had a resurgence at the movies from 2002-2004, and then quieted down again.

How do we define cyberpunk? We tried not to. We pulled our list from as many reliable-looking sources as possible, and only left out things that seemed like obvious outliers. (On the Cyberpunk Review site, some of the movies on the cyberpunk list were listed as having a "low" level of cyberpunk themes, and seemed to be obviously reaching. So we left those movies out.)

So what does this tell us? Maybe cyberpunk is less of a fad than it used to be. Or maybe because we're now living in a cyberpunk era with virtual worlds, nonstop cybersex and evil corporations, we no longer view those things as elements of science fiction. What do you think?