Life span of speakers

Any ideas on the life span of full range speakers in the 5k to 12k price range considering that they were well taken care of in all respects?
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I second Elizabeth's comments but would add that environment makes a significant factor. If stored and used in stable interior climate conditions the life can be well over fifty years.
Speaking from experience, my 33 year old Yamaha NS1000M speakers still look and sound excellent to me.
Usually speakers in the $5000 range last about 4 to 7 years. Speakers in the $12 range last closer to 10 years..