The U.S. private sector added more jobs in December than the previous month, a leading industry report said Thursday. U.S. private companies added 215,000 jobs in December on a seasonally adjusted basis, up from a revised figure of 148,000 a month earlier, according to the National Employment Report released jointly by Automatic Data Processing (ADP) and Moody\'s Analytics. Small and medium businesses accounted for the majority of the employment gains last month, adding roughly 127,000 jobs, while large businesses added about 87,000 jobs in total. By sector, the employment in the service sector rose by 187,000, while jobs in the goods-producing sector increased 28,000, as gains in construction jobs of 39,000 more than offset the 11,000 decline in manufacturing employment, according to the report. \"The job market held firm in December despite the intensifying fiscal cliff negotiations in Washington,\" said Mark Zandi, chief economist of Moody\'s Analytics. \"The job market ended 2012 on a more solid footing.\" The ADP survey is based on data from private businesses totaling more than 23 million workers on payrolls and excludes government job growth. The Labor Department will release the December job report Friday and it may depict a more definitive picture of employment.