This was determined by measuring the year-by-year success of all 30 Major League teams. Ten points were awarded for a World Series championship, five points for a league championship, three points for advancing to a League Championship Series. The teams were also awarded two points for winning a division and one for reaching the postseason as a Wild Card. Thus, a team that won a division title and a World Series would receive the maximum 20 points for that year.
Using that system, the Cardinals compiled 83 points. The Giants (70 points) finished second in the National League and second overall.
The Red Sox topped the American League with 69 points. The Yankees were second in the AL with 64 points.
The Red Sox and Giants have each won three World Series this century, while the Cardinals have won two. But the Cards' season-to-season consistency is unrivaled. They have won eight division titles and four NL pennants over the past 15 years.
Cardinals: 83 points
Red Sox: 69 points
White Sox: 22
Astros: 15 *
Blue Jays: 5
* Houston earned 14 of those points while in the NL
This exercise doesn't pretend to tell us about the future. It isn't weighted toward the recent past, either.
The Yankees' presence near the top of the AL is largely a function of their work through the first nine years of the new century, a period during which they won seven division titles and went to three World Series.
If you had to name a team in the "What have you done for us lately?" category, the Giants would be the obvious choice, with World Series championships in each of the past three even-numbered years.
Dramatic change was possible. Using these same criteria, just two years ago, the Royals would have been shut out. But with two World Series appearances and one championship, they moved into the No. 5 spot in the AL.
On the other side, the Pirates' position at the bottom of the NL does not reflect their current standing in the game. They had the second-best record in baseball in 2015 with 98 victories. They have qualified for the postseason as a Wild Card team for three straight years.
But this was a measurement of teams over time. And finding the Cardinals on top is a valid conclusion for the 21st century's first 15 years of baseball. Over time, they have been the gold standard for organizational strength, and that strength has translated into consistent success at the Major League level.
What this computation also shows us is a dynamic game, with plenty of franchises making their mark at one time or another. Nobody can predict the next 15 years, but this kind of competitive balance has become the calling card of contemporary baseball. The Cardinals have earned the top spot, but even they will have a serious challenge from, yes, the Cubs.