The MasterCard SpendingPulse Retail Dilemma Solved

Stuart O'Sullivan | Stone | Getty Images

The MasterCard SpendingPulse dilemma -- solved.

It has bugged me all morning. MasterCard says retail sales will be up only 0.7 percent this season.

The National Retail Federation (NRF), in an interview on our air, said sales would be up 4.1 percent.

Now, even allowing for different surveys, this is a huge difference.

(Read more: Did the Grinch Steal the Holiday Shopping Season? )

So I asked MasterCard for more specifics on how they analyze their data.

Here is what they told me: "Two points may account for difference," MasterCard spokesperson Marisa Grimes said.

1) "Time period: we are including the week of Hurricane Sandy in these estimates. That had a negative impact on the national figures."

2) "Holiday sectors: We are only including the holiday related categories. The rest of retail nondiscretionary such as food (grocery, restaurants), Gasoline, Building Materials... are not included in the holiday estimate."

Now, that makes a lot more sense. MasterCard data excludes many categories that might have shown a significant bounce. The surveys are not apples to apples.

Who's right: MasterCard or the National Retail Federation?

"It is possible that total retail (ex-auto) that includes all the non discretionary sectors could be up north of 3%," MasterCard's Grimes said. "This broader view was up 4.5% in November," she added.

In other words, MasterCard's more complete view--with all sectors--will likely be close to the NRF estimate.

**Clarification: A previous version of this post mentioned that the MasterCard SpendingPulse survey had been of its card members. However, MasterCard SpendingPulse is a survey of charges from card holders in addition to estimates of all payment forms, including cash and check.