Is wild Pacific salmon worth the extra cost?

In the last 20 years, salmon farming has tripled the world supply of salmon. In 1985, only 6 percent of salmon you'd find at the grocery was farmed. But in 2000, 58 percent came from farm production, according to a University of Albany study.

Farmed Atlantic salmon accounts for 85 percent of all of the world's farmed salmon. Due to the surge in the availability of farm-raised salmon, it's less expensive than wild salmon. In fact, while farmed Atlantic salmon costs $6 to $7 a pound, wild Pacific salmon can cost two or three times that much.

So when should you save and buy the farmed salmon, and when should you splurge on the wild stuff?