Wall Street stocks ticked down in choppy trading while the U.S. dollar and Treasury yields were lower after a new government jobs report showed a slowing but still tight U.S. labor market. Nonfarm payrolls increased by 187,000 jobs last month, the Labor Department said in its closely watched employment report on Friday, slightly below expectations of 200,000 jobs. At the same time, the unemployment rate fell to 3.5% from 3.6% in June. "This is still not the picture of the labor market we would expect to see if the economy were in danger of decelerating dramatically in the short term,...