Need Help Creating a Formula
 

I have a spreadsheet with three worksheets. Each worksheet is for a month.
On each worksheet Column A holds the name and columns b and following hold
the day of the month. Example - cell b2 in all is 1 - hope that makes sense.

I am trying to create a formula that will tell me if 29 consecutive cells
are empty or have something in them. If all 29 are empty then I need the
formula to return a -1.
If there is something in one of the 29 consecutive cells the formula would
not need to return any information. The problem is I need it to count from
worksheet to worksheet consecutively. IE - the January worksheet cell f2
would need to count consecutively through the end of it into the February
worksheet cell c2 (this would count from January 5 through February 2 - which
would be 29 consecutive days). Does anyone know if I can create a formula
that would do this?

I've had success counting the 29 consecutive days when they are one
worksheet, but not when I have to count the days from seperate worksheets.

Thanks for your help!