Caltex Australia continues to generate less money out of fuel refining, with margins in 2014 well below a year ago.

Caltex’s refining margin – the difference between the price of crude oil and its refined fuel products – fell to $US10.51 a barrel in April, from $US11.63 a year ago.

In the first four months of 2014, the margin of $US9.23 a barrel was 30 per cent below $US13.09 in the same period of 2013.

Caltex recently announced its refining business made a $41 million loss in the three months to the end of March.

The emergence of massive low-cost oil refineries in Asia has hurt refining operations in Australia, resulting in planned refinery closures by Caltex and BP.

Caltex Australia shares were down 32 cents, or 1.4 per cent, at $22.00 at 1235 AEST.