Thomas DePaola
(Photo via FanSided)
When looking to evaluate the best and most efficient scorers in the NBA, one of the first statistics that most people would turn to is Field Goal Percentage (FG%). To calculate this stat, simply take the total number of shots a player made, and divide them by their amount of shots taken. The result is Field Goal Percentage - the percentage of shots a player makes while they are on the floor.
Sounds like an optimal statistic for determining a player's scoring efficiency, right?
Wrong.
We tend to use field goal percentage because it’s both easy to calculate and easy to understand. It seems to tell the story of a player’s efficiency with just one number. But the thing is, it’s just too simple.
Allow me to illustrate why:
Imagine I told you that an unnamed NBA player took 10 shots per game and made 4 of them, giving them a 40% field goal percentage. This, by common standards, would be seen as rather inefficient play.
Now, if I told you that a player took 10 three-pointers per game, and made 4 of them, you might think, “Wow, a high volume 40% three-point shooter, that’s incredible!”
See where this is going? Those could very well be the same exact player. Based on simply Field Goal Percentage alone, it is difficult to gauge a player’s efficiency.
Field Goal Percentage Doesn’t Account for 3P Volume
As stated above, Field Goal Percentage’s effectiveness in measuring efficiency decreases as a player shoots more threes. This is relevant because of the recent dynamic shift the NBA has undergone when it comes to team and individual player shot profiles. The NBA has evolved - three-pointers are being shot at a historic rate.
Below is a chart listing the average number of three-pointers attempted per game by all 30 NBA teams in a given season. The chart is sorted from highest to lowest in terms of the 10 most prolific 3 point shooting seasons for the league in NBA history.
Upon review of the chart, you can see that the highest 3PA/G league-wide belongs to the 2020-21 NBA season, which is currently ongoing. Teams are taking more threes this year than ever before, with nearly 40% of all FGA being threes.
It doesn’t stop there, either.
Going down the list, you can see that the number of three-pointers taken by the average NBA team has increased in each of the past 10 seasons. As you can see, threes are being shot at a prolific rate, and so, it is hard to justify using FG% as an accurate assessment of efficiency. This is because taking more threes naturally lowers a player's overall field goal percentage.
Let’s also take a look at individual scoring numbers. Below is a chart containing the shooting statistics of the top 5 scorers per game in the last NBA season. Within this chart, you can see the overall shot profiles of all 5 players, and the percentage of three-pointers they took compared to the amount of two-point attempts they had over the course of the season.
As you can see, the three-pointer accounts for a healthy percentage of each player’s shot profile. In the top 4, all of them take three-pointers at least 35% of the time. Giannis Antetokounmpo, who is known as a very poor shooter, still takes threes nearly 25% of the time he shoots. This goes to show just how important it is for a player to have the three-point shot in their scoring arsenal, as well as how frequently it is used among the league’s top scorers.
Now let’s take a look at the shot profiles of the NBA’s top 5 scorers just 10 seasons ago.
Without even looking too closely, it is clear there is a major difference in the distribution of 2PA and 3PA from just a few seasons ago to now. Only one player, Kevin Durant, took threes greater than 25% of the time. In addition, no player shot under 45% from the field, compared to 2 out of 5 last season. This might lead you to believe that scorers today are less efficient than when they took fewer threes, but that is false.
There has been a great increase in the number of threes attempted by top scorers, as well as an increase in the percentage of threes they take relative to their total FGA. Top scorers have gone from taking threes approximately 20% of the time to now over 40%, doubling the rate they had 10 years ago. This has resulted in increased scoring averages for not just top players, but players all around the league. In addition, efficiency has increased because more threes mean more shots being taken that are worth more points.
The fact that so many threes are being taken by the league’s top scorers is telling. The top 4 scorers last season all shot under 47% on field goals, and two shot under 45%. These could be seen as inefficient numbers for volume scorers, but you must keep in mind that all shot 8+ threes per game.
These players are extremely efficient. It’s just the use of FG% that might make them appear to be less so, at first glance. All of this analysis finally raises the question: If field goal percentage shouldn’t be used as often, what metric should we use?
Alternatives to Field Goal Percentage:
Even though field goal percentage may seem like a statistic that is too commonplace to stop using, there are certainly alternatives that are worthy of entering the mainstream. These methods account for individual shot profiles and give a better idea of just how much a player’s scoring impacts the game on a nightly basis.
True Shooting Percentage:
True shooting percentage (TS%) measures a player's efficiency at shooting the ball. It is intended to more accurately calculate a player's shooting than field goal percentage, free throw percentage, and three-point field goal percentage taken individually. Two- and three-point field goals and free throws are all considered in its calculation.
It is calculated with the following formula:
TS% is more accurate for assessing efficiency because it accounts for the difference in difficulty between 2 and 3 point shots, and uses free throws as well. When using field goal percentage, there is uncertainty when it comes to how many threes a player takes vs how many twos they take. With FG%, all shots are seen as equal, when in reality, that is very far from the truth. Three-pointers are far harder to make than two-pointers, because they are farther away from the basket. True Shooting Percentage factors in the uncertainty we have that 1 FG made could be worth either two or three points, as well as free throws, which are the most efficient part of scoring and are always worth one point. Using this formula means you can separate between the value of each shot and not just count them all as the same.
2P%/3P% Splits As Opposed to FG%/3P%:
If you are looking to have a conversation about basketball and don't have the time to calculate a player’s TS%, there is an alternative that is still more accurate for efficiency than FG%. Instead of displaying a player’s shooting percentages as the commonly-used FG%/3P% split, a more telling metric would be to display 2P%/3P%, alongside their volume from each area on the floor. Some players barely shoot any threes, and their field goal percentage is high because of this. Other players only shoot threes, and their field goal percentage is low because of this. When using these splits instead, a player’s accuracy from both inside and outside the arc is seen, and we can know the full extent of how well and how often a player shoots from all areas of the floor.
Field goal percentage is so simple, and that is its ultimate downfall. It is easy to calculate, but that is what prevents it from truly measuring real efficiency on the hardwood. It seems like it tells the whole story, but in fact, it actually leaves so much of it out. Where does a player shoot from when they are on the floor? Are their shots more difficult than other players? Do they get to the line often? The modern era of basketball is all about getting the most efficient shot, and that is done in a variety of ways. It is important that we factor that into our discussions about scoring efficiency. Now, field goal percentage can still be useful as a benchmark statistic for a player, but in order to conduct a more accurate analysis of scorers, we should explore alternatives to the universally known statistic and try to use other things.
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