“Mad Men,” a chronicle of the advertising industry in the 1960s, is back for its seventh and final season on AMC, with this season’s third episode airing Sunday. I thought it would be fun to look at the many clients “Mad Men’s” central characters have served over the years, and how many of these clients continue to be in business — in the real world.

Companies like Lucky Strike, Dow Chemical and Jaguar have always played a special role in the show, contributing both to the old Madison Avenue setting and advancing the plot. The basic arc of many episodes follows a similar sequence of events: A client has a problem, Don Draper and company work on that problem, character development ensues, and the problem is either fixed or it’s not. Sterling Cooper & Partners, Draper’s latest ad agency home, currently has staffers obsessing over a General Motors Chevrolet contract on all three coasts.

We can see, based on the evolving portfolio of “Mad Men” clients, how the show has caught on with viewers. Of the 15 clients introduced in the first season, seven were either invented for the show or had gone out of business. Compare that to, say, the 23 clients introduced in the fifth, sixth and seventh seasons — with the show by then a bona fide hit. Every single one of those clients was still in business at air time.

It’s also worth noting that many clients featured on the show — Heineken, for instance — also benefit in a promotional way. I tallied up the 83 clients that at any point in the series signed a contract with the main “Mad Men” agency — Sterling Cooper in seasons 1 through 3, Sterling Cooper Draper Pryce in seasons 4 through the middle of 6, and Sterling Cooper & Partners in seasons 6 and 7 — and then determined what’s happened to those companies between the 1960s and today. (I only counted the clients that actually signed on with the agency — so you won’t find Honda, for example, here.)

I did this by reading the detailed episode synopses provided by AMC and looking at this list of clients the show had in season 3. Eight companies (9.6 percent) were invented for the show. Sixty-four clients (77 percent) are still in business in the real world, while 12 companies (14 percent) have been phased out, sold, gone bankrupt or otherwise folded. When it comes to industry, the most common type of client was the kind you’ll find in grocery aisles (24 clients), followed by consumer goods (nine clients) and pharmaceutical (five clients).

Here’s every client that Sterling Cooper (et cetera) ever had:

CORRECTION (April 28, 12:33 p.m.): The number of clients the agencies signed totals 83, not 84, as the blog post previously stated. Also, the Israeli Tourism Board was a pitch and never a formal client. Furthermore, an earlier version said the Sno Ball the team was working on was a Hostess Sno Ball project. It was a Pepsi product; the Pepsi Sno Ball no longer exists. The percentages of type of client and the chart have been updated accordingly.