The *only* folks who know if battletech.com has had reduced traffic are the webmasters over there by looking at log files and traffic. Surely they have some trending information over long term... well, maybe they do, sometimes people don't really care about that kinda data.
Thing is, there are a LOT of search engines. Not just google. There is also, though I can't remember the name of it now, some bar you can install that'll track ratings. But anyway, there is simply no real data on determining how much traffic you are getting. Though we can see a general decline in google rankings, it is by no means an absolute number.
Heck, the dozens of web bots out there can put quite a bit of traffic on your site. Plus, your site may be targeted because you have some old version of a forum software as folks try to hack it, or perhaps people click refresh a lot on your site looking for updates. All of those can lead to a decline in accuracy of actual traffic.
You also have to take into account the numbers themselves. When mac zealots talk about how they have a 50% increase in market share, if the 50% is from 1.5% to 2.25%, it really isn't all that big a deal. So when you look at search engine numbers, if the numbers aren't high enough, and you can see spikes based on single non-worldwide events, the numbers just can't be relied upon anyway.
And we are just talking about the web, which though to some of us it is life, there are people who barely use it out there.
So, the only *real* way we can see how BT, or any other game, has done over time comes down to a single value....
Sales.
This post is all over the place. Based on what you've written, I'm not sure you have a firm grasp how either Google Trends, or general search metrics work. I'll try to help you out a little.
First off, traffic is actual
visitation of the site. Visitation has no part to play in Google Trends, or whether or not a topic is trending. While a spike in Google Trends could include an increase in site traffic, they are not mutually exclusive to one another. Google Trends is not, I repeat, not an indication of site traffic. Sorry.
Google Trends is an indication of search popularity and saturation.
Google Trends tracks how often a particular search-term is entered into Google relative to the total search-volume across various regions of the world. Keep in mind Google Trends only displays the relative combined search volumes from all countries that share a particular language (see "flowers" vs "fluers"). So if BattleTech is spelled differently in other countries (which can be the case in say, Germany), a Google Trends search for "BattleTech" will not include alternate spellings. So if you're looking for an answer accounting for the global total-search volume based on term entered you'd have to include the results from alternate spellings of BattleTech.
(Quick Sidebar: Regional search trend information offered by language variation offers an opportunity to see search-entered terminology in a much smaller sphere.)
Again, all Google Trends will indicate is the search popularity of a particular word, based on the regions where that word shares that particular language. Nothing else.
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Site visitation and search ratings are also two different "things," with site traffic being a component of search ratings.
Site visitation is the number of visitors to your site. A sub-set of visitors includes new and repeat visitors. Search ratings encompass a whole host of neat little variables that search engines use to rank your site within their results. Some information used by these browsers include content, % of visitors, bounce-rate, number of visitors, site architecture, links, meta-date (of various kinds) and usability.
Let's touch on site visitation, and data tracking for visitation for a moment...Visitation data tracking is viewed natively to the site, often with the help of a search engine-offered tool (Read: Google Analytics), since Search Engines are the main gatherers of this type of information.
In relation to BattleTech:
Since bg.battletech is a hosted sub-domain of battletech.com, with the forum boards located in a relative directory within the sub-domain, visitation tracking for battletech.com would provide highly inaccurate traffic information in relationship to the tabletop game, i.e. BattleTech, by itself since battletech.com is about the BattleTech/MechWarrior Universe - not specifically about the board game.
Logging traffic, search and visitor data requires a couple of components (some native, some not, like Google Analytics), properly set up across an entire domain's architecture, which includes sub-domains and accounts for large traffic generators, like the forum. Without a proper setup, your ability to gather accurate statistical data about site visitation and usage is virtually impossible.
How this relates to BattleTech:
Well, if I wanted to track visitation to the BattleTech BOARD GAME site, I'd want to look at the bg.battletech sub-domain and its attached forum. Battletech.com would show the overall visitation for the entire domain, but if I wanted some specific information about BattleTech the board game, I'd have to go deeper.
I'll use OBT as an example. I could drop a Google Analytics Tracking code in the index file of ourbattletech.com. This code would track all data across the entire domain, including the forum, the main site and the various fan sites. It's a great tool if I want information pertaining to the entire domain, but it doesn't really provide the super-detailed information I want about the individual sites. To get deeper into the individual sites, I'd install and setup sub-directory and sub-domain tracking. With site-specific tracking I'm now collecting data points for each site that I can use either in conjunction with the overall domain data, or not. That information can suggest all kinds of improvements or problems I may have been unaware of if I had only tracked the overall domain.
Dynamically generated sites, such as this forum, change daily. This is opposed to the weekly, monthly or yearly changes the other sites visit. For an accurate accounting, lumping one directory in with the rest only offers inaccurate data.
You could also think about it like this. A more specific setup is the difference between looking at the number of people in the USA, Florida and then Orlando. That's the beauty of the IvP4/IvP6. We have the direct address to site-specific traffic data. If I had to wager a bet, I'd bet dollars to donuts that battletech.com sees significantly less traffic than bg.battletech.com, but has longstanding/consistent numbers. It's an easy observation based on content, its relative dynamic, and how often the site is updated.
This is without touching the subject of SEO, or its impact on site visitation/search rankings.
Heck, the dozens of web bots out there can put quite a bit of traffic on your site. Plus, your site may be targeted because you have some old version of a forum software as folks try to hack it, or perhaps people click refresh a lot on your site looking for updates. All of those can lead to a decline in accuracy of actual traffic.
This rarely, if ever, happens anymore.
For example, Google does not count its robot visits (or its competitors) when determining search ranking. That would be self defeating if I wanted to gather and report accurate site traffic wouldn't it?
Robots are ignored by the big search engines when gathering information for ratings, however, smaller search browsers (China has a major culprit here) are not always up to speed on new bots. Their ratings, and how they collect information can be affected, but honestly, who doesn't use one of the big three these days?
As for screw ups in your site architecture (you mentioned hacking, or old software), that's a problem, but not a result. For search ratings, one of the metrics I mentioned is link structure and usability. Out of date links, 404s, 301s, etc., will play a part in the ranking of a site or page. For a website in general, 404s will have a significant impact, as will a 301 if it's not permanent or redirects properly. Old forum software isn't a problem unless spam is prevalent, or if a website's load time is so bad that it impacts usability. Again, I won't even touch the topic of actual site architecture (menus, content, search, etc.), because that would be going overboard. The point is that each of these metrics plays a part in determining search rank.
A slow loading site, with bad links that is covered in spam will reduce your site's traffic because your website sucks. That's the result. Your search engine ranking will reflect how crappy your website is.
To set the record straight:
If you wanted to determine BattleTech's search saturation, you'd check Google Trends
If you wanted to determine BattleTech BOARD GAME's visitation, you'd check the analytics for bg.battletech.com and bg.battletech.com/forums
If you wanted to determine BattleTech's search rating, you'd type in BattleTech in a search engine.
Combined these three things will tell you nothing about the health of a game line. You can make gross assumptions of course, but honestly they're meaningless. (This isn't directed towards you Bad_Syntax)
For a privately owned company you'll "know" the health of a game line because they produce new product. Like many game companies the only indicator that something might be wrong is that one day they'll be open, the next they won't.