In this Nov. 24, 2014, file photo, Philadelphia 76ers' Tony Wroten reacts to a call during the second half of an NBA basketball game against the Portland Trail Blazers in Philadelphia. The winless Philadelphia 76ers are the worst team in the NBA and on another lengthy losing streak for the second straight season. (AP Photo/Matt Slocum)

The Philadelphia 76ers are an extremely bad basketball team, even outpacing how bad the Oakland Raiders are at football. The Sixers are 0-and-17. The Raiders, 1-and-11. Hundreds of millions of dollars in salaries, and you get one win in 28 tries between them.

There's an easy explanation for why that is that is more complex than it sounds: neither team is scoring enough points. Yeah, no kidding. But to find out just how bad they and other poor performing teams are doing, we  pulled data on the most common scores in the NBA and the NFL (and, for kicks, the MLB), and -- surprise! -- both teams are scoring dramatically below the average. (This year, the Sixers scored 91.5 points on average versus their opponents' 105.9; the Raiders scored 14.7 points versus opponents' 28.1.)

Let's start with the NBA, looking at the most common scores (winning or losing):

The most common score in NBA games (looking from January through the postseason) is 102 points, winning or losing. That's all-time; since 2000, the most common score was 99 points. In the 1950s, the most common score was 83 points. You can see how scores from the 1950s are shifted further to the left than the curve on the whole. The next decade, scores spiked, eventually settling back down.

The Sixers are averaging 91.5 points per game this season, and have scored more than 99 points only four times. Their opponents are averaging 105.9 points, and have scored more than 99 points in 12 of 17 games. The average acts as a dividing line.

Likewise the NFL. The graph of the most common scores in the NFL are much more jagged, for the simple reason that NFL scoring takes place in 1-, 2-, 3-, and 6-point increments.

The most common score, though, has been much more consistent. Since the 1960s, the most common winning or losing score in each decade has been 17 points, two touchdowns and a field goal. The Raiders have averaged 14.7 points per game. Their opponents have averaged 28.1. The team has beaten the average only three times -- their opponents have beaten it in every game but two.

And, for no reason other than completeness, here's the graph for Major League Baseball. With 162 games per season, there are a lot more games being considered. And the graph is much, much neater.

Each sport follows a rough bell curve, disrupted in the case of the NFL by the weirdness of trying to score, say, 11 points in a game. Teams that regularly fall on the left side of that curve do poorly. Teams that land on the right side do well.

Our advice to the Sixers and Raiders is simple: Try to score more points than average. Hope that helps.

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