Chart with counts on the regular dates

[#1]

I have a table with structure like the follows:

table:
load * inline
[
  CID, Type, BegDate, EndDate
  1,1,01.01.2010,31.01.2014
  2,2,01.01.2010,25.05.2010
  3,2,18.03.2011,24.06.2013
  4,2,13.02.2012,14.03.2013
  5,1,11.03.2011,15.02.2014
  6,1,13.04.2013,16.11.2013
]

It contains the data about contracts. BegDate can't be null, EndDate can (that means, the contract is active). I need a line chart displaying the number of active contracts of every type on the 1st day of every month beginning from, say, 01.01.2010 and till Today(). If during the month there is no new contracts and no ending contracts it still has to be displayed, it's values are the same as the previous month. As far as I know, I'll have to autogenerate a table with desired dates (the 1st days of months). And what should I do next? Try to populate it with count values during the load process? If yes, how? Or use it as dimension to draw a chart and use set analysis to apply count conditions? Thanks!

[#2]

In other words the Doc, you pointed at, suggests that I would build an extra table with intersections of CIDs and all the dates when these CIDs are valid, am I rigth? And maybe I can build the table with dates corresponding to the beginnings of the months to reduce the data load. But building a new table just to make some counts over it... Damn, didn't expect that...

[#3 · Accepted solution]

Solved for me. I've built an isolated calendar, have taken it's MonthStart(Temp_Date) as MStart and main table's type as dimensions and Count(Distinct if(([BegDate]<=MStart)and(IsNull([EndDate])or([EndDate]>MStart)),CID)) as the expression. It seems to count OK.

The main idea was taken from the author's comments to the topic here http://community.qlik.com/blogs/qlikviewdesignblog/2012/10/16/the-master-calendar