Variable (row number) in IF formula in macro

Version: Excel 2016

Hi there,

I can't figure how to include a variable row number in an IF formula.

I use this to get the last row in OtherFile|Sheet1 and create variable LastRow.

LastRow = Cells.Find("*", Cells(1, 1), SearchOrder:=xlByRows, SearchDirection:=xlPrevious).Row

I then want create an IF formula in the current cell. The IF formula says "if B2 is > the last B cell in OtherFile.xlsx|Sheet1, then return 'New', otherwise; 'Old'".

ActiveCell.FormulaR1C1 = _
        "=IF(RC[2]>'[OtherFile.xlsx]Sheet1'!R2C2,""New"",""Old"")"

So essentially I want a formula that would replace

R2C2

with

RLastRowC2

Any pointers would be much appreciated!

Thanks.