The unemployment rate fell in September to 7.8 percent. That's the lowest level since January 2009 â¿¿ President Barack Obama's first month in office. The rate fell because a government survey of households found a huge increase in the number of people who had jobs.Still, a jump in part-time employment accounted for most of the gain. And a separate survey of employers showed that manufacturing employment dropped by 16,000 in September after falling by 22,000 in August. The weak job market has been a key topic in this year's presidential election, which is down to its final days. Voters will have one final employment report to consider, which comes out four days before Election Day. The economy is not growing fast enough to generate much hiring. Growth slowed to a tepid annual rate of 1.3 percent in the April-June quarter, down from 2 percent in the previous quarter. Most economists see growth staying at or below 2 percent in the second half of the year. The Commerce Department will issue its first estimate of growth in the July-September quarter on Friday.