SINGAPORE - Transport giant ComfortDelGro Corp posted a 12.4 per cent rise in net earnings to $82.5 million for the first quarter despite a dip in revenue.

The profit growth seen in the period ended March 31 was fuelled by lower costs and a huge increase in investment income - from $3.2 million to $13.7 million. This arose mainly from a special dividend from Cabcharge Australia, which was tax-exempt.

If not for this dividend, ComfortDelGro's operating profit shrank by 8.1 per cent to $100.5 million.

Revenue slid by 2.4 per cent to $972 million largely on foreign exchange translation losses led by the weaker British pound.

Group operating expenses shrank by 1.7 per cent to $871.5 million despite increases in major cost components such as staff, depreciation and fuel and power.

On a per share basis, earnings rose from 3.41 cents to 3.83 cents, and net tangible asset backing per share stood at 121.08 cents, up form 114.77.

ComfortDelGro's operating margin before interest, tax and depreciation improved marginally to 20.9 per cent, from 20.6 per cent same time last year.

Overseas businesses accounted for 38.4 per cent of group operating profit, compared with 41 per cent in first quarter last year.

All of the group's transit and non-transit business units posted smaller operating profits. Taxi bore the brunt in absolute terms with a $4.7 million drop to $33.8 million despite lower benefits paid to cabbies in Singapore - a sign that private-hire rivals are beginning to eat its lunch.

The group paid cabbies $13.2 million in benefits, compared with $15.5 million last year.