Cursor-oriented To Dataset Oriented UFX

Hello!
I'm having some trouble with transforming a cursor based (not performing) user function into a dataset-oriented user function.
Actually, I don't even know where to start.

Here is my cursor based function. If anyone has patience to read it and try to understand what I'm trying to achieve, I'd greatly appreciate it.

Data Example:
T_TABLE1
col1 DT_RIF col4
1 12/12/1999 100
1 15/12/1999 110
1 01/04/2004 200
1 01/12/2004 210
1 01/11/2006 220
2 01/01/2005 300
2 01/01/2007 310

Let's say I pass 12/10/2007 to my function. My @NewTable needs to look sth like this
NT_Col1 NT_Col2 NT_Col3
1 1999 110
1 2000 110
1 2001 110
1 2002 110
1 2003 110
1 2004 210
1 2005 210
1 2006 220
1 2005 300
1 2006 300
1 2007 310



ALTER FUNCTION [dbo].[fx_SomeFunction]
(@ParamDateTime datetime
)
RETURNS @NewTable TABLE

(
NT_Col1 NVARCHAR(8),
NT_Col2 int,
NT_Col3 numeric (18, 5)
)
AS
begin


DECLARE @var1 nvarchar(5)
DECLARE @var2 nvarchar(8)
DECLARE @var3 nvarchar(8)

DECLARE @year int

DECLARE @dt_rif_max datetime

DECLARE Curs1 cursor for
select T2.Col1, T2.Col2, T2.Col3, Min(Year(T1.DT_RIF) ) as MinYear
from T_TABLE1 T1, T_TABLE2 T2
where T1.Col1 = T2.Col1
GROUP by T2.Col1, T2.Col2, T2.Col3

open Curs1

Fetch next from Curs1 into @var1, @var2, @var3, @year


WHILE (@@FETCH_STATUS = 0)

begin
while year(@ParamDateTime) >= @year

begin
select @dt_rif_max = max(dt_rif)
from T_TABLE1
where year(dt_rif) = @year
and T_TABLE1.Col1 = @var1

IF @dt_rif_max is not null
select @dt_rif = dt_rif, @var4 = col4
from t_TABLE1
where col1 = @var1
and dt_rif = @dt_rif_max




INSERT @NewTable select @var2, @year, @var4

set @year = @year + 1
end

FETCH NEXT FROM Curs1 into @var1, @var2, @var3, @year;
end


CLOSE Curs1;
DEALLOCATE Curs1;

return

END