Jak się ma taką strukturę to się rzeźbi, czyli najpierw musisz doprowadzić do obrócenia tabeli, aby miała postać: numerumowy, miesiąc, wartość to pozwoli na policzenie rat pozostających do końca i później obrócenie wyniku w drugą stronę, aby dostać oczekiwany wynik:
with nh as (SELECT numerumowy, convert(int,miesiac) miesiac, wartosc
FROM
(SELECT numerumowy, [201804],[201805],[201806],[201807],[201808],[201809],[201810],[201811],[201812],[201901],[201902],[201903],[201904],[201905],[201906],[201907],[201908],[201909],[201910],[201911],[201912],[202001],[202002],[202003],[202004],[202005],[202006],[202007],[202008],[202009],[202010],[202011],[202012],[202101],[202102],[202103],[202104],[202105],[202106],[202107],[202108],[202109],[202110],[202111],[202112],[202201],[202202],[202203],[202204],[202205],[202206],[202207],[202208],[202209],[202210],[202211],[202212],[202301],[202302],[202303],[202304],[202305],[202306],[202307],[202308],[202309],[202310],[202311],[202312],[202401],[202402],[202403],[202404],[202405],[202406],[202407],[202408],[202409],[202410],[202411],[202412],[202501],[202502],[202503],[202504],[202505],[202506],[202507],[202508],[202509],[202510],[202511],[202512],[202601],[202602],[202603],[202604],[202605],[202606],[202607],[202608],[202609],[202610],[202611],[202612],[202701],[202702],[202703],[202704],[202705],[202706],[202707],[202708],[202709],[202710],[202711],[202712],[202801],[202802],[202803],[202804],[202805],[202806],[202807],[202808],[202809],[202810],[202811],[202812],[202901],[202902],[202903],[202904],[202905],[202906],[202907],[202908],[202909],[202910],[202911],[202912],[203001],[203002],[203003],[203004],[203005],[203006],[203007],[203008],[203009],[203010],[203011],[203012],[203101],[203102],[203103],[203104],[203105],[203106],[203107],[203108],[203109],[203110],[203111],[203112],[203201],[203202],[203203],[203204],[203205],[203206],[203207],[203208],[203209],[203210],[203211],[203212]
FROM harmonogramy) p
UNPIVOT
(wartosc FOR miesiac IN
([201804],[201805],[201806],[201807],[201808],[201809],[201810],[201811],[201812],[201901],[201902],[201903],[201904],[201905],[201906],[201907],[201908],[201909],[201910],[201911],[201912],[202001],[202002],[202003],[202004],[202005],[202006],[202007],[202008],[202009],[202010],[202011],[202012],[202101],[202102],[202103],[202104],[202105],[202106],[202107],[202108],[202109],[202110],[202111],[202112],[202201],[202202],[202203],[202204],[202205],[202206],[202207],[202208],[202209],[202210],[202211],[202212],[202301],[202302],[202303],[202304],[202305],[202306],[202307],[202308],[202309],[202310],[202311],[202312],[202401],[202402],[202403],[202404],[202405],[202406],[202407],[202408],[202409],[202410],[202411],[202412],[202501],[202502],[202503],[202504],[202505],[202506],[202507],[202508],[202509],[202510],[202511],[202512],[202601],[202602],[202603],[202604],[202605],[202606],[202607],[202608],[202609],[202610],[202611],[202612],[202701],[202702],[202703],[202704],[202705],[202706],[202707],[202708],[202709],[202710],[202711],[202712],[202801],[202802],[202803],[202804],[202805],[202806],[202807],[202808],[202809],[202810],[202811],[202812],[202901],[202902],[202903],[202904],[202905],[202906],[202907],[202908],[202909],[202910],[202911],[202912],[203001],[203002],[203003],[203004],[203005],[203006],[203007],[203008],[203009],[203010],[203011],[203012],[203101],[203102],[203103],[203104],[203105],[203106],[203107],[203108],[203109],[203110],[203111],[203112],[203201],[203202],[203203],[203204],[203205],[203206],[203207],[203208],[203209],[203210],[203211],[203212])
) AS unpvt)
, hs as (
select
nh.numerumowy
,nh.miesiac
,isnull(k.wartosc,0) w
from
nh
left join nh k on nh.numerumowy=k.numerumowy and nh.miesiac<k.miesiac
)
select
numerumowy, [201804],[201805],[201806],[201807],[201808],[201809],[201810],[201811],[201812],[201901],[201902],[201903],[201904],[201905],[201906],[201907],[201908],[201909],[201910],[201911],[201912],[202001],[202002],[202003],[202004],[202005],[202006],[202007],[202008],[202009],[202010],[202011],[202012],[202101],[202102],[202103],[202104],[202105],[202106],[202107],[202108],[202109],[202110],[202111],[202112],[202201],[202202],[202203],[202204],[202205],[202206],[202207],[202208],[202209],[202210],[202211],[202212],[202301],[202302],[202303],[202304],[202305],[202306],[202307],[202308],[202309],[202310],[202311],[202312],[202401],[202402],[202403],[202404],[202405],[202406],[202407],[202408],[202409],[202410],[202411],[202412],[202501],[202502],[202503],[202504],[202505],[202506],[202507],[202508],[202509],[202510],[202511],[202512],[202601],[202602],[202603],[202604],[202605],[202606],[202607],[202608],[202609],[202610],[202611],[202612],[202701],[202702],[202703],[202704],[202705],[202706],[202707],[202708],[202709],[202710],[202711],[202712],[202801],[202802],[202803],[202804],[202805],[202806],[202807],[202808],[202809],[202810],[202811],[202812],[202901],[202902],[202903],[202904],[202905],[202906],[202907],[202908],[202909],[202910],[202911],[202912],[203001],[203002],[203003],[203004],[203005],[203006],[203007],[203008],[203009],[203010],[203011],[203012],[203101],[203102],[203103],[203104],[203105],[203106],[203107],[203108],[203109],[203110],[203111],[203112],[203201],[203202],[203203],[203204],[203205],[203206],[203207],[203208],[203209],[203210],[203211],[203212]
from
(select numerumowy,miesiac, w from hs) as sc
PIVOT
(
SUM(w) for miesiac in ([201804],[201805],[201806],[201807],[201808],[201809],[201810],[201811],[201812],[201901],[201902],[201903],[201904],[201905],[201906],[201907],[201908],[201909],[201910],[201911],[201912],[202001],[202002],[202003],[202004],[202005],[202006],[202007],[202008],[202009],[202010],[202011],[202012],[202101],[202102],[202103],[202104],[202105],[202106],[202107],[202108],[202109],[202110],[202111],[202112],[202201],[202202],[202203],[202204],[202205],[202206],[202207],[202208],[202209],[202210],[202211],[202212],[202301],[202302],[202303],[202304],[202305],[202306],[202307],[202308],[202309],[202310],[202311],[202312],[202401],[202402],[202403],[202404],[202405],[202406],[202407],[202408],[202409],[202410],[202411],[202412],[202501],[202502],[202503],[202504],[202505],[202506],[202507],[202508],[202509],[202510],[202511],[202512],[202601],[202602],[202603],[202604],[202605],[202606],[202607],[202608],[202609],[202610],[202611],[202612],[202701],[202702],[202703],[202704],[202705],[202706],[202707],[202708],[202709],[202710],[202711],[202712],[202801],[202802],[202803],[202804],[202805],[202806],[202807],[202808],[202809],[202810],[202811],[202812],[202901],[202902],[202903],[202904],[202905],[202906],[202907],[202908],[202909],[202910],[202911],[202912],[203001],[203002],[203003],[203004],[203005],[203006],[203007],[203008],[203009],[203010],[203011],[203012],[203101],[203102],[203103],[203104],[203105],[203106],[203107],[203108],[203109],[203110],[203111],[203112],[203201],[203202],[203203],[203204],[203205],[203206],[203207],[203208],[203209],[203210],[203211],[203212])
) as pt
http://sqlfiddle.com/#!18/5e626/1