A pattern that we see sometimes is that older workers are in what we call “wait unemployment”. That is, they expect to find a job that pays as high a wage as in the previous job, but after a while they realize they can't and so there might be some time spent hoping to get as well paid a job as in the past. That may be one reason behind their longer duration of unemployment.
On March 6th, 2014. See this statement in context.