DECLARE @TodayLastYear AS Date
SET @TodayLastYear = (SELECT dateadd(yy,-1,getdate())

Date     TotalThisYr   TotalLastYr  RunningTotalThisYr   RunningTotalLastYr
1-3-2013     1              1                 1                    1
1-6-2013     0              1                 1                    2
1-7-2013     1              0                 2                    2
1-13-2013    2              0                 4                    2
1-15-2013    0              1                 4                    3

CREATE TABLE t
(
	ID			VARCHAR(25)		NOT NULL,
	Stat		VARCHAR(25)		NOT NULL,
	StatDate	DATE			NOT NULL
);

INSERT INTO t
(
	ID, Stat, StatDate
)

Values
	('1', 'Int', '2012-01-03'),
	('2', 'Int', '2012-01-06'),
	('3', 'Int', '2012-01-15'),
	('4', 'Int', '2012-02-07'),
	('5', 'Int', '2013-01-03'),
	('6', 'Int', '2013-01-07'),
	('7', 'Int', '2013-01-13'),
	('8', 'Int', '2013-01-13'),
	('9', 'Sec', '2012-01-06'),
	('10', 'Sec', '2013-02-01')

CREATE TABLE #t2
    (StatDate           DATE PRIMARY KEY CLUSTERED
    ,TotalThisYr        INT
    ,TotalLastYr        INT
    ,RunningTotalThisYr INT
    ,RunningTotalLastYr INT)

INSERT INTO #t2
SELECT StatDate, TotalThisYr=SUM(TotalThisYr)
    ,TotalLastYr=SUM(TotalLastYr)
    ,RunningTotalThisYr=SUM(RunningTotalThisYr)
    ,RunningTotalLastYr=SUM(RunningTotalLastYr) 
FROM (
    SELECT StatDate, TotalThisYr=1, TotalLastYr=0
        ,RunningTotalThisYr=0, RunningTotalLastYr=0 
    FROM t a
    WHERE YEAR(StatDate) = 2013 AND Stat = 'Int'
    UNION ALL
    SELECT DATEADD(year, 1, a.StatDate), 0, 1, 0, 0
    FROM t a
    WHERE YEAR(StatDate) = 2012 AND Stat = 'Int') a
GROUP BY StatDate
ORDER BY a.StatDate

DECLARE @ThisYr INT = 0, @LastYr INT = 0

UPDATE #t2
SET @ThisYr = @ThisYr + TotalThisYr
    ,@LastYr = @LastYr + TotalLastYr
    ,RunningTotalThisYr = @ThisYr
    ,RunningTotalLastYr = @LastYr
OPTION (MAXDOP 1);

SELECT *
FROM #t2