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Understanding the Top 500 restaurant chains report: Methodology and FAQ

Find out more about the making of the Top 500 report, presented by Nation’s Restaurant News and Datassential, featuring sales, units, average unit volume results for the largest U.S. restaurant chains

The 2021 Top 500 report, presented by Nation’s Restaurant News and Datassential, is the definitive guide to the performance of the largest U.S. restaurant chains. The report is powered by the Firefly 500 Report, Datassential’s ranking of the largest restaurant chains in the United States based on location count. That universe of Top 500 brands is then ranked and analyzed by various metrics including annual sales, unit counts, AUVs and year-over-year percent change for each of those metrics.

Below find more detailed methodology and answers to frequently answered questions about how the Top 500 data is compiled and analyzed.

Got questions about the report that aren’t answered below? Reach out to us. Email NRN editor-in-chief Sam Oches at [email protected] and Datassential industry outreach lead Mark Brandau at [email protected].

Frequently asked questions

How do chains qualify for the Firefly 500?

Chains are included in the Firefly 500 universe based on their year-end unit count, according to Datassential’s proprietary Firefly data platform. Firefly is the firm’s operator database of more than 1.4 million foodservice accounts in the U.S. and Canada, with continually updated listings for all restaurants, on-site locations, and retail food outlets in any trade area.

For calendar year 2020, the location cutoff for the 500th largest chain was 39 units. Initially ranking and sorting by unit count helps Datassential track the fast-rising growth chains that start as strong regional players and have the potential to lead emerging categories. This does cause some high-AUV restaurant brands (typically found in full service) to be left off the Firefly 500 ranking if their unit counts are lower, even if their systemwide sales are greater than other chains that do surpass the location cutoff.

Chains’ locations tracked by Firefly for the purpose of this report are limited to those located in the 50 states and the District of Columbia. Any restaurants in Puerto Rico, Guam, or other United States territories are not part of the calculations, nor are locations on overseas military bases, even if companies publicly report those locations as part of a U.S. or North American system.

How does Datassential compile its numbers?

All location-based data comes from the Firefly database, which aggregates a vast number of information sources available on chains’ online location finders, then cross-references those points with data from location platforms, such as Yelp or Foursquare. Weekly updates of the system track openings and closures of foodservice locations continually.

For sales and average unit volume estimates, the platform uses publicly available inputs such as securities filings for publicly traded companies, Item 19 data from franchise disclosure documents, and industry research conducted by investors and equities analysts.

In cases where restaurant companies share annual systemwide sales, AUV, and year-end unit counts with Datassential, those actual figures replace estimates. Operator-sourced data is vetted by checking numbers against available inputs.

Average-unit volumes are modeled based on available information like Item 19 disclosures, publicly shared sales increases or decreases quantified to the media by a restaurant company executive, prior-year estimates, and third-party industry research sources. From there, algorithms proprietary to Datassential estimate performance based on each chain’s annual change in unit count, the overall performance of the industry segment including that chain, and the overall performance of the primary-cuisine type including that chain. These factors are then weighted by chain size.

When was the data for this year’s Firefly 500 Report collected?

Firefly continually updates location-based data, and the unit counts to determine the universe for this year’s report were compiled for restaurants open as of December 31, 2020. Estimates for sales and AUVs were compiled and calculated during the first quarter of 2021, the same period when fourth-quarter and full-year financial disclosures from publicly traded restaurant companies were compiled.

Why might Datassential’s estimates differ from chain-reported results?

In an operating year like 2020, when the coronavirus pandemic disrupted seemingly everything from dining room restrictions to the supply chain to consumer spending and unemployment, it was more challenging than usual to reconcile assumptions about unit-level performance with actual events. There were significant regional differences in how some states restricted on-premise dining, mitigated the spread of coronavirus, or distributed federal pandemic relief funds, which affected chains differently depending on their national or regional footprint. The rapid closure of underperforming locations, as well as operating days lost to temporary closures, also likely caused variance from typical estimates. Each brand was also different in its response to pandemic restrictions and its ability to adopt off-premise dining strategies like takeout, curbside pickup, or delivery.

Some normal variance between an estimated AUV and actual performance might arise when Datassential calculates an estimate of sales per location with a calendar year-end, which might differ from a brand’s fiscal year-end before or after December 31.

Do sales estimates and performance figures account for sales made by virtual brands or ghost kitchens?

At this time, Datassential does not break out chains’ systemwide sales or AUV by revenue from principal brick-and-mortar brand versus sales from orders for a different brand out of its kitchen. Figures listed in its report are good-faith estimates of sales earned by fulfilling orders of its food from its locations’ kitchens, whether those orders were placed at its point of sale on site, via phone, via a mobile app or online-ordering platform, or through a third-party aggregator or delivery service. Locations that are delivery-only or carryout-only “express” units, with no indoor seating, are included in chains’ unit counts.

When will data be compiled for the 2022 Firefly 500 Report and NRN Top 500?

The data collection period will occur at roughly the same time next year, with year-end unit counts being compiled and confirmed shortly after December 31, 2021. Throughout the first quarter of 2022, Datassential will be in touch with restaurant companies to get operator-sourced unit counts, systemwide sales, and AUV data for the 2020 and 2021 calendar years to analyze growth trends.

How can brands contribute to the research process?

Datassential continually refines and improves its research models and methods, and strives to use as many operator-sourced figures as possible, rather than estimates. Restaurant companies that have not been reached by Datassential at the beginning of Q1 2022 will also be able to submit information via a web form available from Datassential and by Nation’s Restaurant News. The collection period will begin in early 2022 and will last through March 15, 2022.


The Top 500 report is presented by Nation’s Restaurant News and Datassential, using insights from Datassential’s proprietary Firefly platform. Datassential’s Firefly is the ultimate strategic tool — No. 1 operator database, lead generator, customer marketing and intelligence platform, all-in-one. Learn more about getting complete access at

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