"30 Months" duration equals the calendar date range wherein 600 (30 * 20
work days in an average month) days * 8 hours per day * 60 minutes per hour,
minutes worth of working time will have gone past according to the Project
working time calendar, any non-working time not being counted. A calendar
timespan of 3 consecutive weeks running Sun through Sat, 21 days, in which 2
out of every 7 days are non-working (ie, a normal workweek of Mon thru Fri
with Sat Sun off) will be 15 days duration. A timespan from the first of
the month through the last day of the month may be 18, 19, 20, 21, or 22
days duration depending on the day of the week the first falls, which exact
month of the year you're looking at, and in the case of February whether
it's a leap year or not. But a calendar month absolutely will never be 28,
29, 30 or 31 days of duration unless your resources are slaves who never get
any time off whatsoever.
"30 emonths" is the calendar date range during which 900 consecutive 24-hour
days (30 months * 30 average edays per month) have elapsed without any
distinction made between working and non-working days.
"913 edays" is the calendar date range during which 913 consecutive 24-hour
days will have elapsed, no distinction being made between working and
non-working days.
Project always figures duration in minutes, non-working minutes not
counting. In a very real sense there can be no such thing as a 30 calendar
month task per se where the task is defined by its time-frame. Think about
it - tasks are never driven forward by the mere passage of time. Instead
they are driven by resources doing physical activity and the only time
activity happens is when the resource is present and working. If the task
requires X amount of labour to achieve its deliverable, it will span
whatever date range wherein the resource does that amount of activity. That
means the actual date range of that task will span whatever time frame where
the resource will do 30 months worth of whatever is defined as full time
equivalent work in your organization - the actual date range will vary
wildly depending on the resource's time commitment.
A hint - if possible try to avoid tasks that long. A good rule of thumb is
the 8/80 rule which says tasks with a work effort of less than 8 hours are
usually the result of excessive micromanagment while tasks that require more
than 80 hours are too big to manage effectively.
Hope this helps
--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit
http://project.mvps.org/faqs.htm for the FAQs
