The Washington-Baltimore Regional Association can be forgiven for celebrating its recent announcement that the Baltimore-Washington Common Market (BWCM) ranks fifth nationally among major markets in retail sales and total effective buying income.

The 1983 figures, which show the relative rankings of major economic regions, were actually compiled from information contained in Sales and Marketing Management's Survey of Buying Power. Nonetheless, the Survey of Buying Power figures are testimony to WBRA's development as a viable source of economic data for the common market in recent years.

The common market is the term business executives and government officials have used to describe metropolitan Washington, metropolitan Baltimore and the area in between to promote it as an economic entity.

Four years ago, the WBRA projected that the common market would have an effective buying income of $70.6 billion by 1984, a total that would rank it fourth among the top 10 U.S. markets. The 1981 projection represented a 63 percent gain over the 1979 increase for the BWCM.

As it turned out, the WBRA was more conservative in its projections than many believed at the time. The Survey of Buying Power reported that the region actually had an effective buying income total of $69 billion in 1983 -- a 10 percent gain over 1982 but, more important, a total that comes close to matching the WBRA's projection for 1984.

The 1983 figures "reflect the strong economic base in the Baltimore-Washington area, as well as the growing scale of the consumer market," said Charles J. Ruder, general manager of Sears, Roebuck & Co., in a statement released by the WBRA. Indicators point to sustained growth throughout the common market, added Ruder, who is a member of WBRA's board of directors.

WBRA underscored that point by projecting that the Washington-Baltimore region's effective buying income will grow to approximately $110.8 billion by 1988, an increase of nearly 61 percent.

Meanwhile, retail sales in the Washington-Baltimore region totaled more than $31 billion in 1983, according to the Survey of Buying Power. In drawing an economic profile of the region four years ago, the WBRA projected retail sales of $34.7 billion in 1984.

In its 1982 economic profile of the region, the WBRA projected growth of nearly 75 percent in effective buying income between 1980 and 1985. A growth rate of that magnitude would solidify the region's ranking as the fourth-richest market in the United States. We should know a year from now how accurate that projection was, though there seems little doubt that it will be within the ballpark. The organization's projections have been fairly accurate in the nearly five years since it constructed a data base of key economic data for the region.

Since its founding in 1980, in fact, WBRA has gradually developed into one of the most comprehensive and reliable sources of economic data on the Washington-Baltimore Common Market. Requests for information and copies of its publications attest to that conclusion. In 1984, for example, the WBRA received requests for nearly 25,000 copies of fact sheets and other documents on the region's economy. Requests have increased 100 percent over the past three years.

As a catalyst for economic development and as the market research link connecting the Washington-Baltimore communities, the WBRA has proved to be a valuable resource over the years for business location consultants as well as business and government agencies in the region.

That was not the case four years ago. Formed as a nonprofit alliance of business leaders from throughout the Washington-Baltimore Common Market, the WBRA was an organization without a mission or credibility. Although organizers believed it would be useful in promoting economic development within the region, the WBRA was largely ineffective during its first year. Strong parochial interests and genuine concern that the WBRA would duplicate activities already carried out by economic development agencies in various jurisdictions proved to be bigger problems than organizers had anticipated.

To its credit, the WBRA overcame those problems by (1) convincing business and government leaders that the concept of regionalism could be vital to the growth of the Baltimore-Washington corridor, and (2) that the WBRA could serve their needs by acting as a clearinghouse and umbrella organization in promoting economic development.

After several false starts, the WBRA apparently has achieved its initial goal of becoming a catalyst for regional economic development.