On Monday, we noted that Minnesota Vikings receiver Bernard Berrian took to Twitter in defense of his low production this season. When a follower told him he was "wide open at least 5 times," Berrian responded: "been like that the last 4 yrs."

Since joining the Vikings in 2008, Bernard Berrian has caught roughly 50 percent of the passes thrown his way. Otto Greule Jr./Getty Images

One of the fans who challenged Berrian on that point was a Minnesota state representative and a co-author of the team's stadium finance bill. That fact was dramatic but ultimately irrelevant. What concerned me was Berrian's implication that getting open is the extent of his job as a receiver, and beyond that, his production is in the hands of someone else -- presumably the quarterback or the play-caller.

So with help from several resources, I sought out some key facts that would help us understand whether Berrian is justified or if he needs to take more ownership for catching only two passes over the Vikings' first four games.

First, it should be noted that Berrian has been on the field more often than any Vikings wide receiver. According to Pro Football Focus, he has played on 182 of the Vikings' 248 snaps. Michael Jenkins is next with 175 plays, Percy Harvin has 141 and Devin Aromashodu has 36.

On those 182 plays, Berrian has been targeted on 13 passes. ESPN Stats & Information doesn't assign a target when one isn't clear, making its number different from press-box statistics that say Berrian has been targeted 15 targeted times. Regardless, Berrian has caught only two of the 13, or 15 percent.

The top NFL receivers typically catch between 60 and 70 percent of the passes thrown their way, according to a spreadsheet I viewed from ESPN Stats & Information. New England Patriots slot man, for example, Wes Welker has caught 70 percent this season. Houston Texans receiver Andre Johnson is at 71 percent. Steve Johnson of the Buffalo Bills is at 66 percent and the San Diego Chargers' Vincent Jackson is at 65 percent.

Admittedly, 13 targets on 182 plays is a very small number. There are 84 NFL players who have been targeted more than Berrian this season. But this is where his career history, at least with the Vikings, needs to be reviewed for context.

Katie Sharp of ESPN Stats & Information provided the following chart. It shows that in the four years Berrian was referring to, he's caught 52 percent of the passes thrown his way. Since the start of the 2010 season, that number is 45 percent.

There are many factors that go into how frequently a receiver should catch the passes thrown his way. Obviously, quarterback accuracy is one of them. So is the route a receiver is asked to run; a short route is more likely to be completed than one that takes a receiver 30 yards downfield.

But there are some factors that a receiver can control. Does he need the ball delivered precisely to his hands? How good is he at catching imperfect passes? Can he win a physical fight with the defender? To what extent can he twist his body or shield defenders or maintain control after a big hit?

All of these factors go into the pot when evaluating Berrian's past four years. He obviously hasn't gotten as many passes as he would have liked. But over that stretch, he's worked with four different veteran quarterbacks: Gus Frerotte, Tarvaris Jackson, Brett Favre and Donovan McNabb. Have they all inexplicably looked elsewhere when he Berrian was open, presuming he has been? Or did Berrian's extended history of catching about half of the passes thrown his way play a role in their (possibly subconscious) decision-making?

Berrian isn't totally at fault for his two-catch season. McNabb has under-and overthrown him on a number of occasions already. But I hope Berrian doesn't think that getting open is the sole factor in a quarterback throwing his way. That's only half of the battle, and perhaps Berrian hasn't won enough of the other half to justify additional attention. Just a thought.