A modest gain for stocks extended a winning streak into a fourth day. Indexes ended higher on Friday after the government reported another increase in hiring last month, the latest encouraging sign for the US economy. It was the third straight weekly gain for the stock market. The Dow Jones industrial average climbed 62 points, or 0.4%, to 17,006. The Standard & Poor's 500 index added six points, or 0.3%, to end slightly under 2,000. The Nasdaq composite climbed nine points, or 0.2%, to 4,717. (More Dow Jones stories.)