"Small employers tend to report higher HR staffing ratios, while economies of scale help large employers maintain a lower ratio of HR staff to total employee headcount," the authors write. "Smaller employers tend to have higher concentrations of HR managers, but the composition of HR departments at larger organizations tilts in favor of professional and technical staff."

Median figures on HR department composition show professional and technical employees making up nearly half the staff this year, while managerial employees make up a third. Secretarial and clerical workers accounted for 20 percent of HR staff.

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Another record set this year: HR specialization, with 73 percent of HR departments reporting at least one specialist on staff. The most common specialty area is benefits, followed by employment/recruitment, through many specialists tend to wear multiple hats.

HR department budgets continue to grow modestly, according to the report.

"Annual adjustments in HR funding have settled into a pattern of conservative growth in the wake of the Great Recession," the authors write. "These modest HR budget increases are not unlike the economic recovery itself, which has been characterized by slow but steady expansion and very low inflation."

The median HR funding increase this year is 3.7 percent, down from 4.2 percent in both 2015 and 2016. Budgeted HR expenditures dipped to a 10-year low when expressed as a per capita dollar amount. Across all employers, the median amount allotted to HR departments is $1,087 per

employee in 2017, down from $1,440 in 2016.

"A possible explanation is that total spending on the programs and activities overseen by the surveyed HR departments continued growing modestly, but an expansion of the employee population drove down per capita costs," the authors write.

HR salaries are on pace to rise more quickly in 2017. The median hike in HR's staff salary budget is 4.2 percent this year, up slightly from 4.1 percent in both 2015 and 2016, and more than a percentage point higher than the figures from 2012 to 2014. HR staff will likely be getting a median of 2.7 percent of responding employers' total projected wage and salary expenditures for the year – a bigger slice of their organization's overall

compensation pie than seen in prior years.

The most prominent line items in HR department budgets are benefits, employment and recruiting, training and development, and compensation, accounting for nearly two-thirds of HR spending.

Other key findings in this year's study include:

– Nearly three-fourths of employers have formal performance management systems, and HR executives tend to have positive impressions of the programs. Purposes served by the programs range from clarifying expectations and documenting performance to identifying professional development needs and gathering information for decisions on compensation and promotions.

– The practice of tracking HR metrics and analyzing data has become widespread, with more than nine out of 10 HR departments indicating that they employ data analytics of some kind. Broad usage is reported for several types of HR metrics and analytics; for example, compensation and benefits analysis is used by 87 percent of HR departments ''at least occasionally.''

While attitudes about HR metrics and analytics appear generally positive, only one-third of the surveyed HR departments agree that their use of metrics and analytics is adequate.

– The prevalence of HR outsourcing rebounded from last year's all-time low. The 2017 reading shows that 63 percent of HR departments rely on an outside vendor or service provider to handle at least one program or activity.

When handing off programs or activities, most HR departments retain management or oversight of the relationship with the outsourcing vendor.

Less than one in five HR departments said their most recent outsourcing initiative coincided with a reduction in HR staff, which suggests cost savings typically aren't a leading motivation for outsourcing.