EXCLUSIVE: For the first time in more than three years, Broadway’s biggest blockbuster is opening its doors to bus tours, schools from out of town and other groups.

Beginning on Monday, Hamilton offers group sales for performances from Jan. 7 to June 4, 2020, according to a memo the production sent to group sales agents that was obtained by Broadway Journal.

Groups should help stabilize a business that’s recently shrunk ever-so-slightly. Lin-Manuel Miranda’s celebrated musical, which opened in August 2015, remains Broadway’s top-grossing show, averaging $3.1 million a week in 2019. Seats continue to fetch as much as $998 over the holidays, even with two U.S. tours, a London production and engagements in San Francisco and Chicago. (Both are scheduled to wrap up on Jan. 5.)

But in September and October, Hamilton‘s Broadway box office slid 8 percent from the fall of 2018. The average ticket was $259.75 in the seven days ending on Oct. 20, its lowest weekly average in more than two years. (All prices in this story refer to tickets sold at the box office or by other primary outlets, such as Ticketmaster.)

Mike Rafael, a ticketing consultant and analyst, said he believes the recent decline is both specific to Hamilton and to softness on Broadway generally. This season’s grosses overall are off 7 percent from the same point in 2018-19. “They’re dealing with a downturn in the market,” he said. “And hit shows inevitably age.”

A spokesman for Jeffrey Seller, the lead producer, declined to comment.

Each group can buy 20 or more tickets per performance on Tuesdays through Thursdays, from $99 in the rear mezzanine of the Richard Rodgers Theatre (for students attending Wednesday matinees) to $449 “premium” seats. The same prices are available to individual theatergoers, except for the $99 seats.

Although Hamilton isn’t discounting group sales — except for the $99 student seats — it is paying commissions to sales agents for the first three months of 2020. (The standard commission is 9.55 percent.) There are no commissions for sales in April and May, when there are more tourists in New York.

Hamilton last offered tickets to groups in late 2015 for performances through September 2016, but stopped accepting orders as the individual ticket market exploded. A Hamilton assistant company manager told group sales agents in February 2016 that a “presale” offered to American Express cardholders for November 2016 to January 2017 did better than expected, “and, as a result, we’re unable to accommodate groups for that block of performances.” She added in her email: “We’re aiming to be at the Rodgers for a long time, and hope to be able to take care of all of your clients in the future.”

While most shows offer group sales throughout their lives, Broadway has marginalized them in favor of well-heeled individuals willing to pay premium prices. As of July, the producers of Jagged Little Pill designated the first 13 rows of the 21-row center-orchestra section of the Broadhurst Theatre as premium. Groups not inclined to pay $249 and up for tickets are relegated to the far sides and rear of the orchestra, or upstairs.

There’s concern among producers that group sales seats will be resold on the secondary market. According to the Hamilton memo: “Group tickets for clients may not be requested if the intention of the client, or past history of the client, has shown that client intends to sell the tickets not as a group but as individual tickets. Any agent and/or agency that fulfills an order that is not for a bona fide group shall immediately be suspended from accessing any further tickets and all non-group orders will be immediately cancelled.”

The Hamilton Education Program continues, in which low-income public school students and their teachers receive $10 tickets to designated matinees, plus the use of educational guides created by the Gilder Lehrman Institute of American History.

Note: This post was corrected to clarify when Hamilton last offered group sales.