sobre cursores..

[Mithrandir]

Código:

SELECT 
	Año,
	SUM(CASE WHEN Mes = 1 THEN valor ELSE 0 END) AS enero,
	SUM(CASE WHEN Mes = 2 THEN valor ELSE 0 END) AS febrero,
	SUM(CASE WHEN Mes = 3 THEN valor ELSE 0 END) AS marzo,
	SUM(CASE WHEN Mes = 4 THEN valor ELSE 0 END) AS abril,
	...
FROM tabla
GROUP BY Año