Employers spent more for union workers' benefits and compensation, $2.89 and 7.4 percent for total compensation. DB plan costs were significantly higher for union workers, $2.11 and 5.4 percent of total compensation, than nonunion workers, 26 cents and 0.9 percent of total compensation. Defined contribution costs for union workers averaged 78 cents compared to nonunion workers' 57 cents.

The number of employees a company has dictates how much it will spend on employee benefits. For those businesses with fewer than 100 workers, the average spent per worker was 62 cents per hour worked or 2.6 percent of total compensation. For those with 100 to 499 employees, the average paid out for retirement and savings benefits was $1.09 per hour worked or 3.7 percent of overall compensation, which was a lot less than the $2.09 per hour worked, or 4.9 percent of compensation, paid to workers at companies with more than 500 employees.

Defined benefit costs ranged from 23 cents per hour worked for companies with 1 to 99 workers to $1 per hour worked for 500 workers or more. For defined contribution plans, the costs ranged from 39 cents per hour worked for 1 to 99 workers to $1.10 per hour worked for 500 workers or more.

Employer retirement and savings benefit costs for full-time workers in private industry averaged $1.30 per hour or 3.9 percent of total compensation, compared to the 23 cents and 1.5 percent of total compensation for part-time workers. For full-time management, professional and other related occupations, the average was $2.26 per hour worked compared with 71 cents for part-time workers.