US stocks wobbled and finished mostly lower Monday as the price of oil continued to nosedive thanks to the strong dollar. Energy companies took the biggest losses as US crude hovered around $40 a barrel, its lowest price in almost four months, and materials companies also traded lower. Every oil, gas and pipeline company on the Standard & Poor's 500 finished lower as a slump in the price of oil and other fuels extended into a third week. The losses for energy and mining, chemical, and building companies canceled out gains for technology and health care companies. The Dow Jones industrial average fell 27.73 points, or 0.2%, to 18,404.51. The S&P 500 lost 2.76 points, or 0.1%, to 2,170.84. The Nasdaq composite gained 22.06 points, or 0.4%, to 5,184.20. (More Dow Jones stories.)