Say goodbye to a boss; say hello to the never-ending workweek. More and more people are handing in their brass name plates and striking out on their own. But it takes a lot to get a new business off the ground - a lot of money, energy, enterprise, and time. This growing breed of workers, some economists say, could be a factor in why work hours are rising. ``An entrepreneurial lifestyle is one of work, work, work,'' says John Challenger of outplacement firm Challenger, Gray & Christmas in Chicago. ``They have to do everything from soup to nuts. And most entrepreneurs will work over 70 hours a week.'' Take Michelle Devlin. For the past three years, the Houston resident has worked as an independent contractor out of her home for a marketing research company. To bring in a little more money, she, her sisters, and her mother started a business. They buy overstocked merchandise from manufacturers and find buyers for it. It entails plenty of phone calls, research, meetings, and lots of hours. And she's doing it while still working for the marketing research company. She's now putting in 80 hours a week - 12-hour days, plus weekends. ``My goal is to be logged on to my computer for my real job by 8 a.m.,'' Ms. Devlin explains. She works all morning. Takes a 30-minute lunch break, then spends all afternoon on her own business. She breaks for dinner with her husband, then goes back to her market-research work. ``I have to be logged off my computer by 10:30 [p.m.] Texas time. After that the main frame at the company shuts down,'' she says. Once 10:30 p.m. rolls around, she goes back to work on her start-up business and usually doesn't close shop for another couple of hours. ``One of my sisters came over and we were up until 2 in the morning,'' Devlin says. Despite the hours, Devlin's business has yet to turn a profit. But she hopes that will change soon. ``I think it will be the kind of thing where all of a sudden it will happen.'' And she says her hours are hardly unusual among her entrepreneurial friends. ``Everybody's trying to make some more money - they're afraid of retirement - and they want to find some way to get out of the corporate world where they can be their own boss.'' Americans work more . . . Average annual hours worked Country per worker 1990 1995 United States 1,943 1,952 Japan 2,031 1,898 Germany 1,616 1,559 France 1,668 1,631 United Kingdom 1,773 1,735 Canada 1,738 1,737 Australia 1,869 1,876 Finland 1,764 1,775 New Zealand 1,820 1,843 Norway 1,432 1,424 Spain 1,829 1,807 Sweden 1,480 1,544 Figure in 1995 column refers to 1994 data Western Germany Source: OECD . . . and play less Legally mandated paid vacation in European countries Days per year Germany 15 Ireland 15 United States 16 Switzerland 20 Netherlands 20 Belgium 20 Norway 21 France 25 Sweden 25 Finland 25 Austria 30 Spain 30 Average, not legally mandated Source: Economic Policy Institute, ``State of Working America''  