ALGIERS, Aug 24 (Reuters) - Algeria's earnings from energy exports totalled $19.61 billion in the first seven months of the year, up 26.25 percent on the same period last year, customs statistics showed on Thursday.

Energy sales are crucial to Algeria's finances, accounting for some 97 percent of the OPEC member's exports. Oil and gas sales tumbled from $60 billion in 2014 to $35.7 billion in 2015 and $27.5 billion in 2016.

With oil prices between $50-$55 a barrel, earnings for 2017 would be $30-$32 billion, economist Abderahmane Mebtoul told Reuters.

Algeria's foreign currency reserves, which have been falling since the drop in oil prices three years ago, are estimated at about $100 billion. The country's foreign debts are minimal.

(Reporting by Lamine Chikhi; Editing by Aidan Lewis and Mark Potter) ((lamine.chikhi@thomsonreuters.com;))