For a 12 speed, a guess would put it in mid to late 80's...
Bikes can often be dated by serial numbers and components if you are interested.
Even though it is not a Trek, a good way to identify the age of the bike is to look for date codes on the components, and you can get some help listed on Vintage-Trek.com and this will usually help to identify the age of your bike.
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Slow Ride Cyclists of NEPA
People do not seem to realize that their opinion of the world is also a confession of character.
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