In an 83-page plan, conspicuously light on details, Katz said he would make up for the revenue losses by shaving government expenditures by 2 percent, or by $245.5 million total over four years. He would do next to nothing for commuters. Their tax would decrease to 4 percent from its current 4.01 percent.

To achieve his cuts, Katz said, he would change the entire culture of City Hall's workforce to reward workers for doing more with less and for focusing on results such as cleaner streets and more efficiently run recreation centers.

"We have a historic opportunity to change a fundamentally flawed system and give Philadelphians the high-performance government that they deserve and can afford," he said.

The Katz wage-tax plan is a flashpoint in a very competitive mayoral campaign. Despite a robust economy, job growth in Philadelphia has been minimal and residents are leaving at a faster rate than in any other major U.S. city. Many experts say taxes are a major reason, and both Katz and his opponent, Democrat John F. Street, have been pressed to produce a strategy to reverse the exodus and attract business.

Street has said he would follow the Rendell administration's five-year fiscal plan, which he shepherded through City Council. That means he would cut the city's wage tax for residents from 4.61 percent to 4.46 percent and for non-residents to 3.88 percent in 2004.

And since the first televised debate on Oct. 2, he has been goading Katz to release his version of a tax-cut plan. He has used paid media - television and radio commercials - as well as frequent news conferences to ask: "Where's the plan, Sam?"

This plan, Street hoped, would show the essential differences between a Katz or a Street administration. Now he has it and there is little for him to sink his teeth into.

Katz was short on specifics, declining to say whether a single city worker would be laid off or trash route cut.

"I am not going to say with specificity where all the cuts will be made," he said. "I believe that we will be in a very strong position to achieve this tax plan and regrow the economy of Philadelphia."

Yesterday, Street's press secretary, Ken Snyder, likened Katz's plan to "cotton candy," initially sweet-tasting "but not much to it and in the end it's not very good for you."

"There is not one single concrete idea as to how the money is being saved," he said.

About Katz's plan to run the city "2 percent cheaper, 2 percent better," Snyder responded: "If it could have been done, it would have been done."

The city wage tax brings in about $900 million a year - half of all the tax revenue the city collects. When state and federal aid and other revenue are added in, the city's budget totals $2.7 billion.

Street and his supporters, including Mayor Rendell, have said that Katz's cuts would result in draconian cutbacks in city services, in areas such as public safety, sanitation and recreation.

Snyder insisted that Katz's plan would result in at least a $500 million revenue shortfall, saying it did not include a variety of likely cost increases - such as true labor and medical-cost increases.

One specific that Katz did supply was a breakdown of the revenue loss that would result from his plan - $245.5 million total through fiscal 2004. That is nearly $225 million more than Street's plan but nowhere near the $500 million that Street has been claiming Katz's proposals would cost the city.

In arriving at that sum, Katz said, he used the same estimates as the Street plan, including an estimated 2.5 percent annual projected growth rate to account for factors including increased wages.

The Katz plan would result in a $106.9 million revenue loss alone for fiscal 2004, when the wage tax would experience its final cut, to a flat 4 percent. Street's plan, which Katz derided as "creeping incrementalism," would produce a $5.8 million shortfall in fiscal 2004, when the rate would be 4.46 percent.

Katz's plan does not depend on additional revenues based on the assumption that tax cuts will help produce more jobs - "though I believe they will occur," he said.

Katz said his plan would not harm city services. The plan rests on more efficient city government.

The goals of city workers and their managers will be based on answering such questions as: Are the streets cleaner? Are more abused children being cared for? Are more crack houses being shut down?

Right now, Katz said, the city's goals are centered on plugging holes in a budget and responding to crises.

He said this cultural change would require retraining the city workforce. The result, he said, would be a more efficient government.

Essentially, Katz is saying: Trust me.

Asked why people should trust him, he said voters would look at his background as a successful businessman, an adviser to mayors and governors on government finances, and the fact that he had studied how other mayors in Milwaukee and Indianapolis cut spending.

"When a new CEO [chief executive officer] is hired to make a corporation more competitive, he does not come in with the company's internal records and an item-by-item list of what is wrong," Katz explained. "He comes in with a vision and management style."

How will he do it? He will be a "super manager" employing the most modern of management techniques. Every city agency will have its own strategic plan with specific goals that it must achieve. Employees and managers will be rewarded for meeting their goals, and workers will be encouraged to come up with efficiencies. And, he said, people will be fully informed on exactly how tax dollars will be spent in a way that they can understand.

Reaction to the plan was mixed.

One city official with an intimate knowledge of city finances said Katz's revenue estimates seemed accurate but he doubted that Katz could save $245.5 million over four years through more efficient management, especially because Katz refused to project any layoffs.

Bob Inman, an economics professor at the Wharton School at the University of Pennsylvania who has studied city finances, said other cities have cut costs through a number of efficiencies - contracting out services, improved tax collections, better investment policies.

"Two percent doesn't strike me as an excessively large target," he said. "Whether it can be attained with the Philadelphia budget remains to be seen."

David Thornburgh of the Pennsylvania Economy League watched Katz unveil his plan in a meeting room at the Park Hyatt at the Bellevue, at Broad and Walnut Streets. He said Katz's cuts pass the "common sense" test but might not be aggressive enough to attract employers to town.

"I think this is a pretty straightforward, 'do more with less' kind of approach - but not a whole lot less," he said.

One group likely to greet Katz's plan with disfavor is nonresident city workers, who have traditionally enjoyed a lower wage tax rate.

Street's plan would lower the non-resident rate from 4.01 to 3.88 percent. Katz would provide suburbanites who work in Philadelphia virtually no tax relief - from 4.01 to 4 percent in 2004.

Katz said he was unconcerned. Nonresidents' rewards are their ability "to eat at the best restaurants, shop at the best stores," and go to the theater or concerts after work.

He also said equalizing the two wage-tax rates might encourage commuters to move into the city closer to their jobs.

Not everyone would be likely to hold the same view, particularly legislators in Harrisburg, and especially Republicans representing suburban districts, who are sometimes called upon to deliver votes for city funding.

The state law that permits the city to levy a wage tax seeks to ensure that suburbanites bear less of the burden of tax increases because they do not live in the city and do not use city services as heavily as Philadelphia residents. Under the law, when the wage tax is raised, the commuter rate cannot exceed 75 percent of the rate for city dwellers.

But that provision does not apply if the tax rate is lowered. At 4 percent, nonresidents can be taxed at the same rate as city residents.