When Washington lost its last major league baseball team 19 years ago, the metropolitan area had 2.9 million people, households with 29 percent more money to spend than the national average, and an image as a government town recently torn by riots.

Since then, the area has added a nearly a million people and grown even richer, a point certain to be made today when two sets of local entrepreneurs go before the National League Expansion Committee in New York to make their case for bringing baseball back to the Nation's Capital.

But local backers and league officials say Washington also must prove it is more suited to support baseball than it was in 1971, when the Senators packed up for Texas after playing a final game at RFK Stadium with more empty seats than occupied ones.

"It's become a very sophisticated economic center," said Stephen Fuller, professor of urban and regional planning at George Washington University. "It compares with the most vital and most dynamic areas in the country, compares very favorably. . . . {But} we're not viewed as a real city. It's an image problem we haven't overcome."

"The answer to the history question is the future," said Mark Tracz, head of one of the two groups of would-be baseball investors. "The demographic information is very compelling."

Here are some numbers that illustrate the expansion of the local economy:

Washington grew more than 18 percent over the past decade, a rate nearly triple that of the Baltimore region, and, according to the Greater Washington Research Center, at a rate second only to Los Angeles among major cities. In some suburbs, like Loudoun and Prince William counties in Virginia, the growth rate was 49 percent. Growth is predicted to slow during the 1990s, but continue at a healthy pace.

In 1970, the area's average household income after taxes -- so-called disposable income -- was 29 percent above the national average. Last year, that figure, $52,435, was 49 percent higher than the national average, according to Sales and Marketing Management's annual survey of buying power.

In 1970, 39 percent of the area's workers were employed by the federal, state or local governments. Now only a quarter of jobs are government work, providing a more diversified base. The area has more jobs in private industry alone -- 1.6 million -- than the total number of jobs here two decades ago.

The current economic slump has left the real estate market stalled and local businesses laying off workers, but Fuller said the government employment cushions the impact of bad times. He predicted the slowdown would be brief.

One result of the area's economic transformation is the growing number of corporate headquarters, such as the Mobil Corp., which is moving to Fairfax County from New York City. During the booming 1980s, the suburbs acquired Macy's, Neiman-Marcus, Nordstrom and Bloomingdale's. Downtown malls spiffed up, the convention center opened and luxury hotels rose from vacant lots. The MetroRail system, which includes a stop at RFK Stadium, stretched further into the Maryland and Virginia suburbs.

The region, which is the ninth-largest Arbitron-rated television market, ranks higher than its population on many measures of affluence and spending. The area is the nation's fifth-biggest spender on eating and drinking out, according to the buying power survey, and fourth among big cities in the number of households with income above $50,000.

Washington also is rich in baby boomers -- the children born after World War II who make up 55 percent of U.S. baseball fans. A recent study by the Population Reference Bureau said Washington was second only to Denver in the proportion of its population in this age group.

According to a marketing study, the 1990 Scarborough Report, 18 percent of the adult population in Washington and its closer suburbs went to a professional baseball game last year -- more than twice the percentage a decade ago.

Figures show blacks are only slightly less likely than whites to go to baseball games -- encouraging news for the two prospective groups of team owners, which include several prominent blacks.

Staff writer Steve Berkowitz contributed to this report.

POPULATION

1970: 2.9 million.

1990: 3.7 million (preliminary census figure).

DIVERSIFIED JOBS

1971 TOTAL AREA JOBS: 1.2 million (472,000 government jobs, 745,700 private sector jobs).

1989 TOTAL AREA JOBS: 2.2 million (583,200 government jobs, 1,647,700 private sector jobs.)

Source: District Department of Employment Services

1970 AVERAGE HOUSEHOLD INCOME AFTER TAXES: $13,593 in Washington area; $10,565 in U.S.

1989 AVERAGE HOUSEHOLD INCOME AFTER TAXES: $52,435 in Washington area; $35,179 in U.S.

Source: Sales and Marketing Management's Survey of Buying Power

METROPOLITAN WASHINGTON BASEBALL

JOHN "CHIP" AKRIDGE, GENERAL PARTNER: President of the John Akridge Companies, a commercial real estate development and management firm that has developed more than 2.5 million square feet of office space in downtown Washington. A Tennessee native, he has mechanical engineering degree from Georgia Tech and an MBA from Harvard. He moved to the Washington area in 1974, and currently lives in Oxford, Md.

ROBERT PINCUS: President of Sovran Bank/DC National. He has been involved with D.C. Baseball Commission virtually since its inception in the mid-1980s.

DONALD DELL: Chairman of the Board of ProServ, the Arlington-based sports marketing and management firm. A native Washingtonian, he is a co-founder of the Sovran Bank Tennis Classic.

OTHER INVESTORS: Howard Bender, chairman of the board, Blake Construction Co.; Stanley Bender, vice president Blake Construction; acting Republic National Committee Chairman Charles Black and Paul Manafort, partners in Black, Manafort, Stone and Kelly, a public relations and lobbying firm; Democratic National Committee Chairman Ron Brown, attorney; Charles Cocke, Reston, accountant; Robert Cohen, president, Barnes, Morris and Pardoe real estate; Mel Estrin, chairman of the board, University Research Corp. and corporate dealmaker; Allyn Kilsheimer, president KCE Structural Engineers; Gilbert Kinney, vice president Capitol City Associates; Sugar Ray Leonard, boxer; John McMahon, president Miller and Long Co.; Nicholas Paleologos, executive vice president Miller and Long.

CAPITAL REGION BASEBALL

MARK TRACZ, PRESIDENT OF GENERAL PARTNER GROUP: President of Mark Tracz Real Estate, a Falls Church residential real estate firm that had developed more $100 million in residential land. He is president and part owner of the Class A Prince William Yankees and former co-owner of Class A St. Petersburg Cardinals, which hosted spring training for St. Louis Cardinals. A native of the D.C. area, his brother Jack has been involved with front office management of minor league teams for more than 15 years. He lives in Falls Church.

IRA SAUL: Attorney with the Fairfax firm Saul and Barclay, which specializes in real estate development and litigation. He and his wife, Elizabeth Barclay, have developed numerous commercial and residential projects in Northern Virginia. He is treasurer and part owner of the Prince William Cannons.

GENERAL PARTNER GROUP: Tracz; Saul; Bart Fisher, attorney; William Bryant, owner of Bill Bryant real estate; Arthur Ashe, author and former tennis champion; James Brown, announcer for CBS Sports; Arthur Silber, president and CEO of Baltimore-based Sterling Bank and Trust Co. and co-owner of Prince William Cannons; Arthur Watson, former president of NBC Sports; Jerry Phillips, attorney; Phil Tierney, attorney.

OTHER INVESTORS: Unidentified family trust from Northern Virginia will supply majority of group's money; Restructuring Associates, a D.C. firm involved with corporate restructuring, up to $25 million; Thomas Pumpelly, owner PCI Financial Group and former owner of National Tire Wholesale; P. Wesley Foster, president, Long and Foster Realtors; Henry A. Long, chairman and president of Henry A. Long Co. commercial real estate; Paul Shiffman, attorney.