Customers seem to be noticing that Walmart (WMT - Get Report) stores are a little cleaner and staffed with employees who are a little more helpful.

Walmart disclosed during a presentation to associates Wednesday that its clean, fast and friendly customer service scores have increased for an astounding 79 weeks straight. The scores, which measure levels of customer satisfaction, are tabulated by surveying tens of thousands of its shoppers each month. Walmart asks shoppers to tell them about their experience in areas such as check-out, store cleanliness and helpfulness of their employees. 

"It's [paying attention to] the tiny, noticeable things that should be in our DNA," Walmart chief operating officer Judith McKenna told associates at the event. McKenna, who was promoted to the COO position in December 2014, added, "Giving away a smile costs nothing -- people want to feel good."

The improvement in customer satisfaction, which stems from Walmart refocusing on being better at stocking shelves, helping shoppers find items and paying more attention to produce quality, coincides with a decent sales rebound for the retail behemoth.

Walmart U.S. is fresh off delivering its seventh-straight quarterly increase in same-store sales. Same-store sales rose 1%, ahead of Walmart's guidance for a 0.5% uptick. Traffic to Walmart's stores has gone up for six consecutive quarters. 

The company notched success in most areas of its stores, including apparel, health and wellness and groceries.

And Walmart associates may have some extra incentive for ensuring their stores are stocked with the right stuff and customers leave happy.

In March of 2015, Walmart brought back what it calls its Volume Producing Item (VPI) employee incentive program, which was originally introduced by founder Sam Walton in the late 1970s after finding success with aggressively selling moon pies. The goal of the program, says Walmart, is to reward employees for taking ownership of their respective departments by selling items people want to buy. Cash payouts, which Walmart doesn't disclose, are awarded to top-producing workers.