Rouse Co., the Columbia real estate developer, reported that results improved in the third quarter as its shopping centers and office properties shared in the booming economy.

Funds from operations, the most-watched gauge of real estate companies' results, rose 12 percent, to $56 million, from $50.2 million in the same period last year; on a per-share basis, funds from operations rose 8 percent, to 71 cents, from 66 cents on fewer shares. Funds from operations is a financial measure that adds back charges for property amortization and depreciation that otherwise reduce net income.

The company said earnings from its largest division, shopping centers, rose 9 percent, while results at office, mixed-use and miscellaneous properties jumped 42 percent. Earnings fell 4 percent in Rouse's land division, which sells lots in Columbia and Las Vegas.

Revenue in the quarter was $255 million, up 12 percent from $226.9 million. Net income was $26.7 million (32 cents a share), up 36 percent from $19.6 million (24 cents).

For the first nine months of the year, funds from operations was $172.9 million ($2.17), up 12 percent from $154.2 million ($2.03) in the same period last year. Revenue rose 8 percent, to $774.5 million, from $720.3 million. Net income fell 2 percent to $83.6 million ($1.02), from $85.4 million ($1.11).

* Mid-Atlantic Medical Services Inc. of Rockville earned $7.1 million (17 cents a share) on revenue of $335.3 million in the third quarter ended Sept. 30, compared with a loss of $6.7 million on revenue of $299.5 million for the same period in 1998.

Last year's third quarter included a one-time charge, without which the company would have earned $4 million (9 cents).

For the first nine months, the managed-care health insurer earned $17.5 million (42 cents) on revenue of $971.9 million, compared with earnings of $3.5 million (8 cents) on revenue of $888.3 million in the period a year ago.

* Maximus Inc. of McLean earned $7.9 million (37 cents a share) on revenue of $86.7 million in its fourth fiscal quarter ended Sept. 30, compared with earnings of $5 million (26 cents) on revenue of $73.5 million in the year-ago period.

For its fiscal year, the human services outsourcing company earned $27.6 million ($1.32) on revenue of $319.5 million, compared with earnings of $15.5 million (85 cents) on revenue of $244.1 million in fiscal 1998.

* World Airways Inc. of Dulles lost $3.1 million on revenue of $67.5 million in the third quarter ended Sept. 30, compared with a loss of $1.5 million on revenue of $67.5 million in the same period in 1998.

For the first nine months of the year, the aircraft charter company lost $4.7 million on revenue of $200.3 million, compared with a loss of $7.6 million ($1.06) on revenue of $208.3 million.