By Deborah Austin Rainy days aside, Mondays may be improving for executives seeking peak employee productivity. Tuesdays still reign as the most-productive workday, said 48% of executives in a late-2001 Accountemps survey -- similar to results in 1987 and 1998. But 26% percent cited Monday as their employees' most-productive day -- up from 17% in 1998 and 6% in 1987. Monday -- growing as project-launch and "meeting day" -- may seem too hectic to be productive. "But for all those same reasons, it might be considered a very productive day because so much is going on," says Reesa Staten, vice president and director of research programs for Robert Half International, which owns temporary-staffing firm Accountemps, Menlo Park, Calif. Wednesdays are slipping, cited as most productive by only 9% now versus 15% and 19% previously. Thursdays rated 5%, and Fridays -- no surprise -- 1%. Such fluctuations, while normal, may signal workers' need for closer guidance, extra morale boosts or motivation toward week's end, says Max Messmer, Accountemps chairman.