I pieced together a chart that shows homicides by department in Guatemala. The 2010 murder rates use population figures from
here. I then estimated 2.5% population growth for the 2011 data. FOR 2012, I just used the homicide rates from Carlos Mendoza at
CABI. He also has 2011 murder rates.
The department of Guatemala has really experienced significant improvement in the last few years. That's driving down overall homicide rates for the entire country. As you can see here, the rate has dropped from 78 per 100,000 in 2010 to 54 in 2012. That still makes it one of the more violent departments.
The Peten, Alta Verapaz, and Baja Verapaz have also seen big drops since 2010 though Peten was flat from 2011 to 2012 (maybe up 1).
Like every country, there is a great deal of variation from department to department. We'd also see similar variation within departments and cities.
Here's the data another way.
While Guatemalans tend not to perceive an improved security situation in the country, changes in the homicide rates tell a different story.