Counting working days excluding holiday and weekends

What I need is a formula to include date and time for determining how long work items are being completed in.

Here is some sample data:
Start Date and Time End Date and Time
Work Create Datetime Work Completed Datetime Work Elapsed Time (in Sec)
4/28/14 9:31 5/1/14 11:39 363
4/28/14 9:31 5/1/14 11:48 160
4/28/14 9:33 5/1/14 11:57 93
4/28/14 9:34 4/28/14 13:23 50
4/28/14 9:36 5/1/14 12:26 359
4/28/14 9:37 5/1/14 9:26 65
4/28/14 9:45 4/28/14 11:47 128

I need to have the duration for amount of days to complete the task.

Any help is greatly appreciated.

you can use networkdays()

NETWORKDAYS
Returns the number of whole working days between start_date and end_date. Working days exclude weekends and any dates identified in holidays. Use NETWORKDAYS to calculate employee benefits that accrue based on the number of days worked during a specific term.

NETWORKDAYS(start_date,end_date,holidays)
http://office.microsoft.com/en-gb/ex...005209190.aspx

Look up the syntax for NETWORKDAYS. It does exactly what you want. In essence it's =networkdays(start date, end date, range of cells containing holidays). You'll probably need to reformat the date/times to show only dates. If you're stuck, upload a spread sheet containing some examples and a list of holidays...

try
=NETWORKDAYS(A2,B2)+((B2-A2)-INT(B2-A2))

from this post, added by cbatrody
http://www.excelforum.com/excel-form...-weekends.html

does this work better
=NETWORKDAYS(A81,B81,Holidays!A1:A7)-1-MOD(A81,1)+MOD(B81,1)
was not sure about the hours part
http://www.exceltip.com/excel-date-t...two-dates.html
http://chandoo.org/wp/2010/09/10/working-hours-formula/

excellent - thanks for the rep