VBA loops

In your example:

C2: =COUNTA(B2:B366) = 365
D2: =COUNTIF(B2:B366,0) = 317
E2: =365-COUNTIF(B2:B366,0) = 48
F2: =D2+E2 = 365

If you drag these formulae down, they will give a 365 "rolling" total.

Code to fill the range D2:D366

With Range("D2:D366")
    .FormulaR1C1 = _
        "=COUNTIF(RC[-2]:R[364]C[-2],0)"
    .Value = .Value
End With

And column E:

With Range("E2:E366")
    .FormulaR1C1 = _
        "=365-COUNTIF(RC[-3]:R[364]C[-3],0)"
    .Value = .Value
End With

Regards, TMS