Heavy Traffic Synchronous Digital Reference Cost Calculator
*The "Mean salary of librarians per hour is taken from
Table 2-1 of the National Compensation Survey: Occupational Wages in the
United States, July 2002, U.S. Department of Labor, Elaine L. Chao,
Secretary, Bureau of Labor Statistics, Kathleen P. Utgoff, Commissioner.
September 2003. Bulletin 2561. Available at:
http://www.bls.gov/ncs/ocs/sp/ncbl0552.pdf (accessed November 6, 2003). This
value was then adjusted from 2002 Dollars to 2003 dollars using the Inflation
Calculator available at: http://www.bls.gov/ (accessed November 6, 2003).
Link
to Normal Traffic Digital Reference Cost Model
Formulas used for calculations:
"Reference transactions per month charged" equals the quantity,"Numbers of hours of service per week" times "Number of service point" times 60 minutes per hour times 52 weeks per year, end quantity, divided by the quantity, 12 months per year times "Average length of reference transaction in minutes," end quantity.
"Labor cost of meetings (assuming 1 hour
meetings) per year" equals the "Number of committee/task force/work group
meetings per year" times the "Average meeting attendance" times the "Mean salary
of librarians per hour."
"Cost of software per year" equals the "Number
of service points" times the "Cost of software per year per seat."
"Cost
of software per minute of service" equals the "Cost of software per year"
divided by the quantity, 49 (assumes a 49 week year with 3 weeks of suspended
service) times 60 times the "Number of service hours per week," end
quantity.
"Mean salary for librarians per minute" equals "Mean salary for
librarians per hour" divided by 60.
"Estimated labor cost per reference
transaction" equals the "Average length of the reference transaction in minutes"
times the "Mean salary for librarians per minute."
"Estimated total
compensation per reference transaction (with fringe benefits)" equals the
"Estimated labor cost per reference transaction" plus the quantity, "Estimated
labor cost per reference transaction" times 28.3 divided by 71.7, end quantity.
Note that 28.3 divided by 71.7 is the ratio of benefits to wages and salaries.
Both numbers were cited in Employer Costs for Employee Compensation
Summary for June of 2003 available at:
http://www.bls.gov/news.release/ecec.nr0.htm (accessed November 4,
2003).
"Estimated total labor compensation per month" equals the
"Reference transactions per month" times the "Estimated total compensation per
reference transaction (with fringe benefits)."
"Estimated total labor
compensation per year" equals the "Estimated total labor compensation per month"
times 12 months times 49 weeks divided by 52 weeks.
"Estimated total
cost per year" equals the "Labor cost of meetings (assuming 1 hour meetings)
per year" plus the "Cost of software per year" plus the "Estimated total labor
compensation per year."