SQL POWER And Decimal Pricision Help

Hello all, I am having a lot of trouble maintaining decimal precision in the script below.  Specifically, the statement:  SELECT @SKIPPROB = 1-(POWER(.999,@CURRENT - @LASTHIT)).  This should be returning a large decimal value, but some of the values that are being updated into the Straights table keep showing up incorrectly rounded - sometimes as whole numbers. In one particular example, the statement above would become...
 1-(POWER(.999,10201)).  Note: 10201 is the result of @CURRENT - @LASTHIT. This should then equate to 0.99996306 as the answer to the formula. For some reason, when I open the Straights table, the result shown is 1.00000000.  Please note that the result is loaded into the variable @SKIPPROB which is declared to be a Decimal(10,8). Also, the column in the straights table that this value is updated into is also set as Decimal(10,8). I am still very new to this, so am I overlooking something. I don't understand why the result is being rounded up to 1.00000000. Any help is appreciated.

DECLARE @EXACT INTEGER, @CURRENT INTEGER, @LASTHIT DECIMAL(10,5), @AVGSKIP decimal(10,2), @MAXSKIP INTEGER, @1000AGO DECIMAL(10,4), @HITS1000 DECIMAL(10,4), @HITSLIFE DECIMAL(10,4), @SKIPPROB Decimal(10,8)

SET @EXACT = 1000

WHILE @EXACT > 0

BEGIN

SET @EXACT = @EXACT -1

SELECT @CURRENT = (SELECT MAX(GAME) FROM History)

SELECT @LASTHIT = (SELECT MAX(GAME) FROM History Where EXACT = @EXACT)

SELECT @AVGSKIP = (SELECT AVG(cast(exactskip as decimal(10,2))) FROM HISTORY WHERE EXACT = @EXACT)

SELECT @MAXSKIP = (SELECT MAX(EXACTSKIP) FROM History WHERE EXACT = @EXACT)

SELECT @1000AGO = (SELECT MAX(GAME) FROM History)-1000

SELECT @HITS1000 = (SELECT COUNT(EXACT) FROM History WHERE EXACT = @EXACT AND GAME > @1000AGO)

SELECT @HITSLIFE = (SELECT COUNT(EXACT) FROM History WHERE EXACT = @EXACT)

SELECT @SKIPPROB = 1-(POWER(.999,@CURRENT - @LASTHIT))

UPDATE Straights

SET [CURRENT SKIP] = @CURRENT - @LASTHIT,

[AVG SKIP] = @AVGSKIP,

[MAX SKIP] = @MAXSKIP,

[TIMES DUE] = (@CURRENT - @LASTHIT)/1000,

[FLIPS] = (@CURRENT - @LASTHIT)/692.8005,

[HITS 1000] = @HITS1000,

[PERCENT 1000] = (@HITS1000 / 1000)*100,

[TOTAL HITS] = @HITSLIFE,

[PERCENT LIFETIME] = (@HITSLIFE / @CURRENT)*100,

[SKIP PROB] = @SKIPPROB

WHERE EXACT = @EXACT;

END