Net profit in 2012 was $72.6 million, compared with $4.56 billion profit in 2011, Cairn said in a statement.
The big profit in 2011 was mostly on account of the company selling majority stake in its Indian unit, Cairn India to mining group Vedanta Resources.
Cairn had net cash of about $1.6 billion at the end of last year.
It still holds 10 per cent of Cairn India, valued at about $1.1 billion.
"We are very happy with the balance we have created in the portfolio," Cairn Energy Chief Executive Officer Simon Thomson said.
"We are well positioned to continue our strategy in 2013 and beyond."
Cairn said it bought a 65 per cent working interest in three offshore blocks in Senegal from FAR Ltd and will become the operator. The company plans to drill at least one well in the next 18 months in the area that has prospects of more than 1.5 billion barrels of oil.
The three contiguous blocks -- Rufisque, Sangomar and Sangomar Deep -- are currently operated by FAR with Senegal national oil company Petrosen.
FAR is an independent Australian Securities Exchange
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