Calculate number of days on/off in a continuos work system per month - SUMIFS??

[M Frs]

Hello,
[TABLE="width: 500"]
<tbody>[TR]
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[TD][TABLE="width: 64"]
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[TD="class: xl85, width: 64"]off days[/TD]
[/TR]
</tbody>[/TABLE]
[/TD]
[TD]12[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]A[/TD]
[TD]B[/TD]
[TD]C[/TD]
[TD]D[/TD]
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[TD][TABLE="width: 64"]
<tbody>[TR]
[TD="class: xl85, width: 64"]work days[/TD]
[/TR]
</tbody>[/TABLE]
[/TD]
[TD]30[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]Start[/TD]
[TD]End[/TD]
[TD]days[/TD]
[TD]type[/TD]
[TD][/TD]
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[/TR]
[TR]
[TD]01/01/2015[/TD]
[TD]12/01/2015[/TD]
[TD]12[/TD]
[TD]off[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]13/01/2015[/TD]
[TD]11/02/2015[/TD]
[TD]30[/TD]
[TD]work[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]12/02/2015[/TD]
[TD]23/02/2015[/TD]
[TD]12[/TD]
[TD]off[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]24/02/2015[/TD]
[TD]25/03/2015[/TD]
[TD]30[/TD]
[TD]worl[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
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[/TR]
[TR]
[TD][/TD]
[TD]work[/TD]
[TD]off[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]Jan[/TD]
[TD]19[/TD]
[TD]12[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]Febr[/TD]
[TD]...[/TD]
[TD]...[/TD]
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[/TR]
[TR]
[TD]Mar[/TD]
[TD]...[/TD]
[TD]...[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]...[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
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[TD][/TD]
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I need to calculate the on/off days of a continue work system within a particular month. The continue work system is 30 days working, and than you get 12 days off, but I need to bring that into months (Jan/Feb/...) while the work system exceeds the month end limits. The file needs to be flexible so that it can be also 30 days, 14 days or any other combination.
I have a column A with the start date, column B with the stop date after 30 days, than the next row, is the start date of the 12 days off, and in column the end date. Column C calculates the days (12 or 30) and column D gives the description on the work system (working or off), column D is in fact the same as column C. As you can see, I'm not a wizard in this things, so I hope I don't seem stupid asking the same kind of question, but the additional difficulty to the SUMIFS questions already answered on this website is that the # of days is a range, not 1 particular day. I actually don't know whether I will need to use SUMIFS or any other formula.

I don't know whether I could add the file to this forum, but it doesn't seems like.
Can someone assist me in the formula? In case I was not clear explaining my issue, please come back to me.

 

[M Frs]

Hi Everybody,

It seems to be a difficult request as nobody answered yet.
Can you have a look into this as I need it quite urgently? Or am I not clear enough?


Thanks