How do you calculate work hours for a year?

The answer following may be relevant in a consulting environment, but is not correct for the typical so-called 9-5 worker/employee. There are more than 52 weeks in a year: 52 X 7 = 364; most years have 365 days, and leap years have 366. If we define "work hours" as all hours on "pay status," meaning days worked as well as days away from active duty due to paid leave for holidays, while sick, on vacation, etc., the number of work hours in a year varies depending on where that extra day (two in leap years) falls. Thus the # of U.S. work hours in a given calendar year ranges from 2080 to 2096. Examples: Most employers consider standard "work days" as Monday-Friday; for a typical full-time employee working 40 hours per week, if the "leftover" day in that calendar year falls on: Saturday or Sunday >>> the # of work hours = 2080
Monday through Friday >>> the # of work hours = 2088
A leap year has 2 "leftover" days; if they fall on:
Saturday AND Sunday >>> the # of work hours = 2080
Friday and Saturday >>> the # of work hours = 2088
Sunday and Monday >>> the # of work hours = 2088
any two weekdays (M-F) >>> the # of work hours = 2096
This is applicable to workers with different schedules, but who work 40 hours or 5 days out of 7; it just depends on whether that extra day (or two) is one of their scheduled workdays or not. It's true for regular part-timers too; for someone working 20 hrs/week, or 50% time, the number of work hours in a year would vary from 1040 to 1048. This is a negligible point to many, but to legions of hard working payroll staff, especially those who don't have regular pay periods (like every other Friday), but one that varies (say, once a month), it is crucial. Over many years, the # of work hours averages out to be a little over 2087, so it is not unusual to see 2088 in common use. Along the same lines, the # of work hours in a month can vary from 160 to 184, because a month of 28 to 31 days can have from 20 to 23 weekdays (20 x 8 = 160; 23 x 8 = 184). I hope this is useful, and apologize if I unintentionally stepped on any electronic toes.

________________ (The calculations below are for the United States. The numbers may vary significantly for other countries.) A normal work week for most jobs is 8 hours a day for 5 days. There are 52 weeks in a year but most workers get a two week vacation. So, 8 X 5 X 50 = 2000 hours worked in a year. Many companies also give 10 holidays, which brings it down to 8 x 5 x 48 = 1920. Many companies also give 5 days of sick/personal time per year, which brings it down to 8 x 5 x 47 = 1880. Finally, if you are calculating how much time people actually spend on their job (as opposed to company meetings, bathroom breaks, surfing the Internet, etc.) a common metric is 80%. Therefore, if you are looking for how many hours you can expect someone to actually be productive in a year, 8 x 5 x 47 x .8 = 1504 hours is a reasonable maximum. This is an important number when you are dealing with billable hours in a consulting environment.