Try below..Modify it as per your need.

;WITH Abstraction(pYear, pMonth, pValue, jan,feb,mar,april,may,june,july,aug,sep,oct,nov,decb) AS

(

SELECT 1999

,12

,cast (0 as float)

,cast (0 as float)

,cast (null as float)

,cast (null as float)

,cast (null as float)

,cast (null as float)

,cast (null as float)

,cast (null as float)

,cast (null as float)

,cast (null as float)

,cast (null as float)

,cast (null as float)

,cast (null as float)

UNION ALL

SELECT CASE WHEN pMonth = 12 THEN pYear + 1 ELSE pYear END

,CASE WHEN pMonth = 12 THEN 1 ELSE pMonth + 1 END

,pv.pvalue

,case when pmonth = 12 then isnull(jan,0.0) + pv.pvalue else ISNULL(jan,0.0) end as jan --this value is for jan if the pmonth is 12 and simialrly below

,case when pmonth = 1 then isnull(feb,0.0) + pv.pvalue else isnull(feb,0.0) end as feb

,case when pmonth = 2 then isnull(mar,0.0) + pv.pvalue else isnull(mar,0.0) end as mar

,case when pmonth = 3 then isnull(april,0.0) + pv.pvalue else isnull(april,0.0) end as april

,case when pmonth = 4 then isnull(may,0.0) + pv.pvalue else isnull(may,0.0) end as may

,case when pmonth = 5 then isnull(june,0.0) + pv.pvalue else isnull(june,0.0) end as june

,case when pmonth = 6 then isnull(july,0.0) + pv.pvalue else isnull(july,0.0) end as july

,case when pmonth = 7 then isnull(aug,0.0) + pv.pvalue else isnull(aug,0.0) end as aug

,case when pmonth = 8 then isnull(sep,0.0) + pv.pvalue else isnull(sep,0.0) end as sep

,case when pmonth = 9 then isnull(oct,0.0) + pv.pvalue else isnull(oct,0.0) end as oct

,case when pmonth = 10 then isnull(nov,0.0) + pv.pvalue else isnull(nov,0.0) end as nov

,case when pmonth = 11 then isnull(decb,0.0) + pv.pvalue else isnull(decb,0.0) end as decb

FROM Abstraction a

cross apply(select cast (RAND(CAST(CAST(NEWID()AS VARBINARY) AS int)) * 1000 as float) pvalue) pv

WHERE CASE WHEN pMonth = 12 THEN pYear + 1 ELSE pYear END <= 2005

)

SELECT

pYear,pMonth,pValue,

case

when pmonth = 1 then jan

when pmonth = 2 then feb

when pmonth = 3 then mar

when pmonth = 4 then april

when pmonth = 5 then may

when pmonth = 6 then june

when pmonth = 7 then july

when pmonth = 8 then aug

when pmonth = 9 then sep

when pmonth = 10 then oct

when pmonth = 11 then nov

when pmonth = 12 then decb

end as problem

FROM Abstraction

where pYear>= 2000