While the characters on HBO's Game of Thrones face ice zombies, food shortages and life-changing revelations, everyone involved with the show's production can be mighty pleased. Its blockbuster success has made a global phenomenon of a bestselling fantasy book series with a cult following, and the network owned by AT&T Inc. (T) has even greenlit a prequel since audiences can't seem to get enough of author George R.R. Martin's world.

It's tricky to define and measure what success to a franchise like this is, but we've tried by analyzing five different parameters. (no spoilers for Season 8, we promise)

1.Eyeballs

If it feels like there's more Game of Thrones chatter every time a new season airs, you're not wrong. Everyone's favorite tale of feuding families reached a ratings high with the premiere of the latest season, but it has been adding more viewers consistently since its first season. In fact, it became HBO's biggest hit back in 2014 when it surpassed The Sopranos' record of 18.2 million weekly viewers in 2002.

2.Google Search Interest

Google naturally sees a spike in people looking up "Game of Thrones" every time a new season airs. What's interesting, however, is search interest has been growing.

This isn't common, as you can see from the search interest in other popular drama television shows.

The Game of Thrones fandom kept getting bigger, and the show kept generating more buzz. And buzz is important, especially for premium cable networks that don't depend on advertising for revenue. As June Thomas, the senior managing producer of Slate podcasts, wrote, "Popular 'buzz,' a uselessly fuzzy concept for channels that make money from ad sales, is important to HBO and Showtime (CBS) because it generates subscriptions—the more a show like Game of Thrones dominates the cultural conversation, the more people will sign up for HBO to watch it. Ideally, every show will receive a) critical praise, b) a huge audience, and c) a shelf full of statuettes. But in a pinch, just one of those things will suffice."

3.Piracy

Game of Throne has had a piracy problem for years, with millions scouring popular torrent and streaming sites for episodes soon after they air (and sometimes before, in case of a leak). Season 7 of the show exceeded one billion illegal downloads and streams across piracy channels by September 3, 2017, according to the digital piracy experts at MUSO.

HBO doesn't seem too desperate to clamp down on this, however, since all views seem to be good views. During a 2013 earnings call, former Time Warner CEO Jeff Bewkes joked that being the most pirated show is "better than an Emmy," according to Business Insider. "...it's a tremendous word of mouth thing, the issue would be if they were doing it and because they could get it not subscribing, we don't see much of that," he said. "Our experience is, it all leads to more penetration, more paying subs, more health for HBO, less reliance on having to do paid advertising — we don't do a whole lot of paid advertising on HBO, we let the programming and the views talk for us — it seems to be working."

4.Emmy Awards

Speaking of Emmys, Game of Thrones hasn't been doing shabbily on the awards front either. The show has enjoyed tremendous critical acclaim, a rare feat for a violent fantasy drama.

5.Game Earnings

In the first year after its release in October 2017, Game of Thrones: Conquest, a mobile strategy game based on the series, grossed more than $125 million worldwide on the App Store and Google Play, according to Sensor Tower. The market analyst says the game showed consistent sequential month-over-month and year-over-year growth in revenue, with a compound monthly growth rate of 14.8% during its first year. It spent more than 25 weeks in the App Store’s Top 50 grossing iOS apps, peaking as the no. 1 free-to-play strategy game in the U.S., according to a statement from Warner Bros. Interactive Entertainment and HBO Licensing & Retail.