As members of Congress look forward to a potentially delayed start to the annual August recess, many congressional observers are once again raising the concern that lawmakers do not spend a whole lot of time on Capitol Hill doing the people’s business. For example, the House was in session for 131 days last year, while the Senate met for 165 days.

In recent years, House members from both sides of the aisle have proposed mandating members of Congress to spend MondayFriday in Washington. In 2014, Rep. David Jolly, R-Fla., lobbied for a change in the House rules to require lawmakers to commit to 40-hour workweeks in D.C. The following year, Rep. Scott Peters, D-Calif, introduced a bill that called for a similar change.

Proponents of the five-day congressional workweek insist that such a mandate would result in both increased productivity and increased bipartisanship since members can get to know each other better within each chamber. The most common proposal calls for members to spend three consecutive weeks in Washington, followed by one week in their districts or states for constituent matters.

Arguments in favor of the five-day workweek imply there is a problem that did not exist before: namely, that members used to spend more time in Washington and less time in their states and districts. However, data suggest that the amount of actual time members spend in Washington has been fairly consistent for more than four decades. The number of hours the House and Senate have spent in session has held steady—a little below and a little above 2,000 hours, respectively—since the early 1970s.

While the number of actual work hours in Washington has stayed consistent over the last 40 years, the number of important bills passed by both chambers—our measure of Congress’ legislative productivity— is only about a third of what it was in the early 1970s. While congressional productivity is clearly trending downward, it’s not at all clear that adding days in Washington would solve the problem. One must instead question why Congress’ productivity is declining, even as they spend roughly the same amount of time in D.C. as their predecessors.

In her landmark works, University of Maryland Professor Frances Lee explains why members might be less focused on policy than politics. Before the 1980s, Republicans in Congress perpetually occupied the minority (in the House, the GOP was in the minority uninterrupted from 1955-1995). Because achieving majority status in either chamber was unlikely, Republicans were forced to cooperate and compromise with Democrats to ensure Republican policy views were represented. Since the 1980s, however, majority status in Congress has become much more uncertain and competitive, with continuous flips in control back and forth between the two parties. This has necessitated a strategic shift in Washington activity away from cooperating on policy goals and toward actions of obstruction designed to portray the majority party as incompetent. The consequence is that a much lower proportion of legislators’ activity in Washington is actually related to the business of legislating.

A second reason for decreased productivity may be that members are not as well-resourced as in the past. Lawmakers’ bevy of legislative assistants and directors are responsible for monitoring policy activity, drafting legislative proposals and amendments, and coordinating coalitions across member-offices to advance legislation. Put simply, policy staffers are the behind-the-scenes workers who execute the vital responsibilities of legislative research, creation and passage in Congress.

Since the mid-1980s, however, the number of congressional staffers has decreased significantly. As a point of comparison, in 1987, Congress employed more than 8,000 aides in Washington. By 2015, the number had shrunk to just over 5,000, a decline of 33 percent. This has forced lawmakers to stretch their capacity more than in previous decades.

The data reveal that the clear downward trend in the number of important bills passed since 1979 is mirrored by the falling number of staffers based in Washington; both have fallen by more than 30 percent. Quite simply, if there are fewer aides available to draft and advance policies, fewer bills will be signed into law, particularly on important issues where coalitions are harder to formulate. Further, this decline in staffing resources is compounded by factors like dramatic growths in population, the size and scope of the federal government and the number of issues Congress is expected to address.

It is possible, though not proven, that extended work periods in Washington might assist in raising the level of personal familiarity, and perhaps even a modicum of trust among ideologically opposed members. However, the political incentives toward a more confrontational politics, in combination with severely limited congressional capacity, may well continue to far outweigh such potential gains. Solutions to the competitiveness and staffing issues are in short supply in such a highly partisan environment, but simply keeping members in Washington for longer periods of time is not an effective silver bullet.