Spanish construction group Ferrovial, owner of London's Heathrow airport, said Tuesday its net profits plunged 43 percent in 2012 after major one-off gains the previous year.
"The 42.9 percent decline in net profit is attributable to the extraordinary gains obtained in 2011," which totalled just over one billion euros, it said in a statement.
"A significant portion of that figure did not represent a cash inflow since it was attributable to the revaluation of Heathrow Airport Holdings," Ferrovial said.
The company recorded a net profit of 709.7 million euros ($950 million) for 2012, down from a total 1.243 billion euros in 2011.
Having sold off part its stake in the operator that controls Heathrow in 2011, Ferrovial sold off more in 2012.
"The company divested a total of 16.34 percent of Heathrow Airport Holdings in two transactions, providing Ferrovial with capital gains of 186 million euros," the statement said.
The company said earnings strengthened particularly at Heathrow and its other prize asset, Canadian toll road 407 ETR.
"The company's businesses outside Spain performed well and offset declines in the domestic market resulting from the economic situation," it added, referring to Spain's long recession.
Heathrow registered a record 70 million passengers in 2012, it said.