This is an economic indicator you never hear about (and it's sending a warning sign)

Restaurant traffic is seemingly a good indicator of how the economy is doing. Eating out is certainly a luxury and it's one of the first things consumers cut back on when they're uncertain about the economy.
That's why I'm surprised that no one in markets ever talks about the Restaurant Performance Index from the National Restaurant Association.

Some highlights:

• For the first time in nearly three years, restaurant operators reported a net decline in same-store sale
•  Restaurant operators reported a net decline in customer traffic results in December
• The overall outlook for the economy from restaurant operators was the worst in 3 years