The Celtics have shown they’re willing to spend big in order to sustain long-term success. They’ll return their entire top six, plus the vast majority of their role players.

It appears likely that the 2024-25 roster will feature at least 12 – if not 13, 14, or 15 – of the same players as the 2023-24 championship team.

How common is that? Let’s take a closer look.

2023 Nuggets into 2024: Five of the top six playoff scorers returned, but Bruce Brown did not. Ten of the 14 players from the playoff roster came back, but four headed elsewhere. Denver finished second in the West and lost in the Western Conference semifinals.

2022 Warriors into 2023: All six of the top playoff scorers returned, but four of the 14 on the roster did not. Golden State ended up sixth in the West and also lost in the Western Conference semifinals.

2021 Bucks into 2022: All of the top six playoff scorers returned, but the back end of the roster looked almost entirely different as eight of 17 playoff participants didn’t come back. Milwaukee was third in the East and also lost in the conference semifinals.

2020 Lakers into 2021: Four of the top six scorers returned, but Rajon Rondo and Danny Green did not. Six of the 15 playoff participants didn’t come back the following season, as the Lakers finished seventh in the West and fell in the first round.

2019 Raptors into 2020: This was an unusual situation, where Finals MVP Kawhi Leonard elected to join the Clippers in free agency. Green also headed to the Lakers in free agency, which thrust Pascal Siakam and Fred VanVleet into expanded roles. Five of the 14 players from the championship roster didn’t return, and Toronto claimed second in the East before also losing in the conference semifinals.

2018 Warriors to 2019: The Warriors, the last team to repeat in 2017 and 2018, returned all six of their top scorers in 2019. Five of the 15 playoff participants weren’t back in the mix. Golden State finished first in the West before enduring a string of bad injury luck and falling to the Raptors in the Finals.

2017 Warriors to 2018: The 2017 Warriors were one of the most dominant teams of all-time. Kevin Durant, Stephen Curry, Klay Thompson, Draymond Green, and Andre Iguodala all returned, but sixth-leading playoff scorer Ian Clark (not many would guess it was him) did not. Just three of the 14 who played in the playoffs didn’t come back the following year. Golden State repeated as NBA champions.

So, what are the takeaways here?

For starters, repeating is quite difficult. The Warriors were the last team to do so, six years ago, and no other franchise has come particularly close since. Talent around the NBA is higher than ever, and the league is structured to promote parity.

At the same time, it can be done. Much like the Warriors, the Celtics developed homegrown talent, swung big and succeeded in free agency and trades, and assembled role players that fit around those stars.

Continuity doesn’t necessarily guarantee success, but it doesn’t hurt. Each of the last five NBA champions before the Celtics has lost in the conference semifinals or earlier, in part because of changes to the roster.

The final takeaway is that maintaining a roster that’s essentially the same is very uncommon. The 2019 Warriors had their top six back, but five other players didn’t return. The 2020 Raptors didn’t keep their centerpiece. The 2021 Lakers lost wily veterans. The 2022 Bucks and 2023 Warriors became one year older and lost much of their depth. The 2024 Nuggets lost a key piece in Brown.

So, don’t take this for granted. It doesn’t happen often. The Celtics have a prime window to win more titles and a shot to join the Warriors as one of the most dominant dynasties of this millennium.