LINCOLN, Neb. (AP) — Lincoln police say the number of rapes and attempted rapes reported in the city last year was the highest seen in at least the last 25 years.

Police received 188 reports through November, a 23 percent increase over the 152 cases reported in all of 2014.

The number has climbed steadily since the mid-2000s, when police investigated an average of 110 sexual assault cases a year. The FBI says the number of reported rapes statewide has increased since 2000, even as the total number nationally has fallen.

Police and advocates say they don’t know what’s driving the increase. It’s possible that more victims are reporting rapes than in the past.