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Dec 19 (Reuters) - Caltex Australia Ltd (CTX) said on Tuesday it expected its full-year underlying profit to rise as much as 18.3 percent, helped by strong growth in premium diesel sales.
Net profit "on a replacement cost" basis was expected between A$600 million ($460 million) and A$620 million ($475.29 million) for the year ending Dec. 31, up from A$524 million in the same period a year earlier, the company said in a statement.
Caltex said net profit on a replacement cost basis was a better measure of the company's performance as it excluded the impact of fluctuations in oil and product prices.
It added that it expected total transport fuel sales volumes of 16 billion litres, a marginal improvement over the same period last year.
"Strong growth in premium retail diesel continues to drive growth in total premium fuels, reflecting an overall trend of petrol substitution with diesel," the company said in a statement.
Caltex, however, flagged lower retail margins in the second half, compared with the first, citing increased retail competition and rising commodity prices.
Caltex said its Brisbane-based Lytton refinery was expected to contribute earnings before interest and tax of about A$310 million during the period, a more than 50 percent growth over last year.
Last week, Caltex said it will continue to be Woolworths' fuel supplier after an Australian regulator opposed BP's buyout of Woolworths' gas stations, easing concerns among investors that Caltex may lose a chunk of its earnings if the deal were to go through.
Caltex's shares were 0.6 percent lower by 2355 GMT while the local energy index .AXEJ gained 0.5 percent in a higher overall market. ($1 = 1.3045 Australian dollars)