A recent Barron's story reported that traffic at Whole Foods has declined by 3% in the past 18 months, which translates to 12 million transactions, or the equivalent of 88 lost transactions per day, per store (assuming the average customer spends $36 per store trip).
"... The magnitude of the traffic declines, when discussed in numbers (not %) are staggering," according to Barclay's analyst Karen Short. "To be more specific, as most retailers know, once traffic has been lost, those patterns rarely reverse."
Kroger seems to be the main culprit, as its organic food sales are now about the same as Whole Foods' organic food sales (although it has many more stores). Plus, nearly half of all Whole Foods stores are within three miles of a Kroger, which typically has cheaper prices for natural groceries.