NEW YORK — Sony Corp. reports that Sony BMG Music Entertainment posted a fourth quarter net loss of $61.8 million on sales of $962 million for the three months ended March 31. Results for the joint venture include $92 million in restructuring charges before taxes. Sony claimed an equity net loss of ¥3.1 billion ($29 million) from the joint venture for the quarter. Comparable figures from a year ago for the joint venture were not available. In Sony's fiscal third quarter Sony BMG recorded net income of $21 million on sales of $1.5 billion, including a $168 million pre-tax restructuring charge. From the start of the joint venture on Aug. 1 to the end of Sony's fiscal year, Sony BMG has posted a net loss of $66 million on sales of $3.3 billion, including pre-tax restructuring charges of $290 million.