Move formulas on tab copies

[RockiesRachel]

I have the following problem:

I am trying to work on new timesheets. 

Each pay period is on a separate tab. On each tab you have a cell with Overtime carried over. The formula for this is =SUM('PP16'!I37+'PP16'!I38).

When copying the tab, I am hoping that the formula is moving to PP17 (=SUM('PP17'!I37+'PP17'!I38). Is there a way to do this? 

Thank you!

Rachel

[#2]

@RockiesRachel 

Where is the formula, in PP16 or in another sheet?

[#3]

@Sergei Baklan : The formula is on a tab called PP16, the cell it is referring to is on a different tab called PP15.

I want to copy the tab PP16 to another tab that I will be renaming PP17. Then the formula reference needs to change to PP16 and so forth.

Below is a screen shot but I am not sure if you can see enough.

Thanks for your help,

Rachel