Washington (CNN) - Members of Congress have received between 200% to 1,000% more constituent mail in the last decade than they ever have before, says a report released Tuesday.
The report, titled "Communicating With Congress: How Citizen Advocacy is Changing Mail Operations on Capitol Hill," found that on average, Senate offices reported a 548% increase in mail volume since 2002, while House offices reported a 158% increase.
The largest increase came in 2009, when the average increase in constituent mail was 865%. The study points to the heightened activity in the Congress, in particular the economic stimulus, health care reform and cap and trade, as the reasons for the dramatic increase.
The increase in mail is putting new pressures on congressional staff, too.
According to the study, "a majority of staff report they spend more time on constituent communications than two years ago (58 percent); and 46 percent report shifting resources to manage increased volume."
Even with staffers spending more time responding to correspondence, the time in which it takes for constituents to get a response remains high.
The report says that according to 42 percent of staff, " it requires more than three weeks for the office to draft and approve a response to a constituent raising an issue that previously has not be raised."
The reason for the long response time depends on whom you ask.
The report states that 41% of mail staffers, people tasked with specially responding to mail, said the review and approval process for an outgoing piece of correspondence is the biggest challenge in getting responses out quickly.
Senior managers, the staffers who work through review and approval process, said "the amount of mail we need to respond to" is the biggest problem facing their response time.
The Congressional Management Foundation collected the data for this study in 2005, 2010 and 2011. Congressional staffers were invited to participate in the study via direct email to all House Chiefs of Staff and Senate Administrative Directors. The study had 260 respondents.