MADRID, June 15 - Spain posted a current account deficit of 1.561 billion euros in March, down from a shortfall of 2.094 billion euros in the same month last year, the Bank of Spain said on Friday. In the first three months of the year, the accumulated deficit stood at 2.671 billion euros, compared with a deficit of 3.155 billion euros in the January-March period in 2000, the bank said in a statement.