By Brendan O'Brien
MILWAUKEE (Reuters) - A single bullet hole.
Surrounded by peeling orange paint. Marked by a small plaque inscribed with "We Are One" and "8-5-12."
While diminutive, it is a powerful reminder to those who come now to pray here of the carnage that descended on this Sikh temple nearly five months ago. A white supremacist went on a rampage, killing six worshipers and wounding four, including a police officer, before being shot by police and then taking his own life.
"We left one bullet hole to remember them ... to honor them by," said Kanwardeep Singh Kaleka, 29, a nephew of one of the victims and a member of the Sikh Temple of Wisconsin in Oak Creek, a suburb of Milwaukee.
"This is the one we wanted to keep to remember that day and what happened. For us, it was a very important day for all of us here. It changes our perspective on things," he said.
As they search for a way to cope with their loss, to remember and to honor the massacre's victims, Kaleka and his family and fellow congregants share a profoundly melancholic bond with hundreds of others from around the United States who survived or lost loved ones in one of the year's other shooting rampages.
In a country that averages nearly 11 shooting deaths per day -- more than 12,000 people were killed a year in gun-related homicides or accidents on average between 2008 and 2010, according to the Brady Campaign to Prevent Gun Violence -- 2012's mass shootings have a distinct and tragic hue if for no other reason than the everyday nature of their locations.
In addition to the six dead in Oak Creek, the year's tally includes:
* Four killed in an Atlanta day spa in February
* Five killed at a Seattle coffee shop in May
* Six killed at a Minneapolis sign company in September
* Seven killed at an Oakland religious college in April
* Twelve killed and 58 wounded in a Denver-area movie theater in July
The most shattering of all, however, was also the year's last: Twenty six killed -- including 20 first graders and six adults -- at Sandy Hook Elementary School in Newtown, Connecticut.
"Particularly schools, Sandy Hook, when you are talking about kindergartners or first-graders being mowed down, that is something that is almost unimaginable," said Robert Sampson, a professor of social sciences at Harvard University.
In all, 140 people were killed or wounded in seven mass shootings in 2012, making it the bloodiest year for these types of incidents in modern U.S. history, according to an accounting by Mother Jones, the liberal-leaning magazine.
But as the nation struggles to come to grips with these horrific episodes and continues to grapple with its gun-control policies, researchers say it is too early to say if 2012 marks a broader trend of increasing mass shootings in the United States.
"There have been some years when there have been spikes and other years when there have been low points, but you can't say because we had one year in 2012 of a number of high profile cases that this is a trend. It's not," said Northeastern University criminologist James Alan Fox, who writes a blog about crime and the justice system for the Boston Globe.
During the last 35 years, there has been an average of about 20 shooting rampages annually with about 100 casualties, according to Fox, who uses a broader definition of a mass shooting than Mother Jones.
"Some years we have several large ones and those are the times when people start talking (whether this) is a new thing, an epidemic. It's not. Because the following years, things are quieter," Fox said.
(Editing by Dan Burns and Phil Berlowitz)