Because of a transposition of some figures, earnings data from United Virginia Bankshares Inc., reported in the Business & Finance section last Tuesday, were incorrect. For 1979, the bank holding company's operating profits were $29.6 million ($5.50 a share), compared with $25.6 million (4.74 a share) a year earlier, a gain of 16 percent. Fourth-quarter operating profits rose to $8 million ($1.48 a share) from $6.8 million ($1.26 a share).

United Virginia Bankshares, First Virginia Banks and National Banks of Washington yesterday reported substantial increases in profits during 1979, as regional banks benefitted from a larger loan business and higher interest-rate profit margins.

Ethyl Corp., of Richmond, also reported sharp gains in sales and earnings.

For UVB, the state's largest banking company, operating profits rose to $14.1 million ($1.35 a share) in 1979 from $11.6 million ($1.10) the previous year. Fourth-quarter operating profits, which do not include gains or losses from selling securities in UVB's investment porfolio, rose to $3.5 million (33 cents) from $3 million (29 cents).

Chairman Joseph Jennings said his company's record performance reflected a growth in commercial and installment loans and controls over non-interest expenses.

Average loan volume increased 10 percent to an average $1.8 billion while total assets edged up 3 percent to an average of $3.08 billion during the year. UVB's performance in 1979 translated into a 16.8 percent return on stockholders' equity (stock investment).

First Virginia Banks, a Falls Church-based bank holding company, reported 1979 operating profits of $14.1 million ($1.35 a share) compared with $11.6 million ($1.10) in 1978. Fourth-quarter operating profits rose to $3.5 million (33 cents) from $3 million (29 cents) a year earlier.

Chairman Thomas Malone said total deposits were $1.3 billion and assets were $1.46 billion on Dec. 31 -- both up 7 percent in the year.

National Bank of Washington, the third-largest D.C.-based bank, said 1979 net income rose to $6.9 million ($5.00) from $6 million ($4.35) in 1978. Fourth-quarter earnings were $1.51 a share vs. $1.32 a year ago.Assets rose 7 percent to $923 million and loan volume increased 15 1/2 percent to $536 million.

Union First National Bank, the Washington flagship bank of Financial General Bankshares, reported 1979 net income of $6.1 million ($2.66 a share) compared with $5.4 million ($2.38) in 1978. Assets rose 5 percent during the year to $673 million on Dec. 31 while loan volume jumped 10 percent to $345 million.

Ethyl Corp., a manufacturer of petroleum and industrial chemicals, said earnings last year $97.5 million ($4.77 a share) compared with $82.7 million ($4.02) in 1978, an increase of 18 percent, as sales increased 16 percent to $1.66 billion. Fourth-quarter profits rose to $22 million ($1.07) from $20.5 million (99 cents).

Robertshaw Controls Co., a Richmond-based manufacturer of control devices, reported 1979 earnings of $8.6 million ($2.20 a share) compared with $12.5 million ($3.20) the previous year. The 1979 figures include a one-time charge of $2.6 million (66 cents) against earnings, reflecting an agreement in principle last year to settle civil antitrust suits. Sales rose to $327 million from $304 million.

Smithfield Foods Inc., a Virginia meatpacking firm, said 1979 earnings were $3.4 million ($1.43 a share) from continuing operations, compared with $6.6 million ($2.66) the previous year -- which included $3.86 million from continuing businesses and $2.7 million from discontinued operations. Operating earnings actually rose to $1.43 a share from $1.08 since the 1978 continuing operations had included a $1.2 million tax credit. Sales rose to $193 million from $171 million. Fourth-quarter profits rose to $1.7 million from $1.2 million.