A new survey is giving Walmart very low marks. 

The American Customer Satisfaction Index ranks the mega-retailer dead last for customer service.  Walmart also earned the distinction of having the lowest score of any supermarket. 

Walmart's bad numbers come as customer satisfaction with retailers rises for the third year in a row to an all-time high.  Rite-Aid, CVS, Walgreens and Macy's rounded out the bottom five.