When it comes to job interviews, more candidates are showing they've done their homework on a potential employer, recruiters say.

According to a survey of 150 human resource, finance and marketing managers developed by Accountemps, a Menlo Park, Calif.-based staffing service, 79 percent said that interviewees were showing evidence of at least some research on their company. The number is up from 59 percent ten years ago.

By contrast, job candidates demonstrated only slightly more knowledge of employers in their cover letters, the survey found. Only 44 percent of recruiters said cover letters today showed a deeper knowledge of their companies than in the past.

"By learning as much as they can about a company before interviewing, prospective employees demonstrate resourcefulness and a sincere interest in the job," Max Messmer, chairman of Accountemps, said in a statement.

He added that cover letters and resumes were often deciding factors in granting an interview, so applicants should make an effort to "present a compelling case" in writing.