Celtics three-point shooting:
last year/this year/since Dec 1st
Tatum: 37.6%/36.4%/34.6%
Brown: 35.4%/32.2%/30.1%
White: 39.6%/38.5%/34.6%
Holiday: 42.9%/34.5%/34.6%
Horford: 41.9%/36.0%/29.8%
Hauser: 42.2%/37.4%/41.3%
Porzingis: 37.5%/34.9%/36.0%
Pritchard: 38.5%/41.4%/38.7%
7 of their top 8 rotation players are shooting worse from three this year than last, and its been especially bad in the stretch since December 1st. Alot of the issue they are having is they just can't seem to make shots. Got to think water will eventually find its level with the shooting.
It's likely a volume and shot quality issue. The Celtics have been jacking up a ton of bad shots this season, all for the sake of taking more 3's per game. We're talking off the dribble, contested 3's early in the shot clock without passing the ball. I can understand emphasizing 3's, but they should come within the flow of a good offense. These shots are not that. They're bad shots. Low percentage shots.
More driving, inside out basketball that leads to open 3's will result in better percentages.
The data doesn't really back this up either.
Looking at NBA.com/s tracking data, last year the C's took 36.8 of their 42.5 threes per game with 4+ or 6+ feet of separation from the nearest defender. Thats 86.6% of their threes were open or wide open. This year its 41.6 of 48.6 threes a game, or 85.6%. So although they are taking more threes, they've generally been the same amount of open.
What HAS changed is the make rate. Last year they were 38.8% on open threes and 41.6% on wide open threes. This year its 36.3% on open threes and 38.5% on wide open threes.
Once again the issue isn't type of shot. It isn't chucking. Its not poor decision making. It's just that they are missing shots they made last year. It's really that simple.
The team has two issues right now:
1) Shooting slump
2) Crunch time defense has been bad.
At the same time, we've gone from taking fewer than five contested threes per game to more than seven. Those contested shots are taking the place inside shots. That's probably a couple points per 100 possessions that we're giving away.
Okay, let's do the math.
Let's say two shots in the restricted area become two contested threes per game. C's shoot about 70% on restricted area shots. That would be 2.8 ppg. If you shoot two extra "tight" threes per game instead at 30% you score 1.8 ppg. So really at worst the C's are maybe sacrificing 1 ppg by skewing their shot selection more towards threes.
Their PPG has declined in raw terms 2.6ppg since last year. So even IF you think they are chucking too many threes it appears there's some greater issue besides shot selection.
I don't disagree that the C's could stand to shift their shot profile slightly back towards drives and paint shots. But the main issue remains they are shooting poorly. Lats year they shot 38.8% from three, this year 36.2%. The reason the Cav's look unbeatable this year? A 40.1% mark from three. In the last 9 years only 1 team has cracked 39.2% from three for a year, the clippers in the bubble season shot 41.1%.
Well, your mathematical analysis didn't take into account who is doing the shooting, the spots we are shooting from, how soon in the shot clock we are shooting, etc. Not all "open" 3PAs are good shots.
Looking at who is shooting
% of all team threes they took last year - % of all team threes they've taken this year
Tatum: 17.5% - 19.4%
Brown: 11.8% - 10.9 %
White: 14.2% - 17.1%
Holiday: 9.2% - 9.1%
Horford: 7.4% -8.6%
Hauser: 13.4% - 8.9%
Pritchard: 11.0% - 16.7%
KP: 8.4% - 4.9%
So the only huge drops are Hauser and Porzingis (because they've been injured). But that slack had largely went to White and Pritchard, who are two of your better shooters. So it's not a "who is shooting" issue either.
As for where their are shooting: Last year 21.9% of their threes were from the corner, this year its 20.8%, so not a huge difference there either.
Neither of these things is surprising. On a large enough sample size its very rare that stuff like shot selection or who is shooting will change a lot year to year (barring injury). The threes a team shoots are somewhat self-weeding, teams WANT to take good shots and so they tend to converge on shooting shots that are open by guys that can make them. So actually, in most cases open threes are in fact good threes since teams will tend not to want to take bad shots at all.
