CREATE TABLE [dbo].[SinfRegister] (
	[idNumber] [int] IDENTITY (1, 1) NOT NULL ,
	[hora] [datetime] NULL ,
	[requerente] [nvarchar] (50) COLLATE Latin1_General_CI_AS NULL ,
	[requisitante] [nvarchar] (50) COLLATE Latin1_General_CI_AS NULL ,
	[responsavel] [nvarchar] (50) COLLATE Latin1_General_CI_AS NULL ,
	[titulo] [nvarchar] (100) COLLATE Latin1_General_CI_AS NULL ,
	[descricao] [nvarchar] (500) COLLATE Latin1_General_CI_AS NULL ,
	[categoria] [nvarchar] (50) COLLATE Latin1_General_CI_AS NULL ,
	[prazo] [datetime] NULL ,
	[pendente] [bit] NULL ,
	[data_conclusao] [datetime] NULL ,
	[estado] [nvarchar] (50) COLLATE Latin1_General_CI_AS NULL 
) ON [PRIMARY]

SELECT     responsavel, COUNT(responsavel) AS ntarefas
		FROM         dbo.SinfRegister
		WHERE     (pendente = 1)										
		GROUP BY responsavel

SELECT     responsavel, COUNT(responsavel) AS ntarefas
		FROM         dbo.SinfRegister									
		GROUP BY responsavel

id |responsavel|pendente
1	jcanosa	0
18	voliveira	0
19	jmatias	0
20	voliveira	0
21	voliveira	0
22	jbarros	0
23	voliveira	0
25	jbarros	0
26	jmatias	1
27	jcanosa	0
28	voliveira	0
30	jcanosa	0
31	nadia	      1
32	jmatias	0
33	jbarros	1

responsavel|pending|total
__________________________
jmatias    |   1   |   3
jbarros    |   1   |   3
jcanosa    |   0   |   3
nadia      |   1   |   1
....

SELECT   responsavel, 
         Sum(CASE 
               WHEN pendente = 1 
               THEN 1 
               ELSE 0 
             END) AS [Pending], 
         Count(responsavel) AS [Total] 
FROM     Sinfregister 
GROUP BY responsavel

		 SELECT t.responsavel
		 	  , dt1.pending_tasks
			  , dt2.all_tasks
			  , dt2.all_tasks -  dt1.pending_tasks AS completed_tasks
		   FROM 
				(SELECT DISTINCT responsavel t
				   FROM         dbo.SinfRegister) AS t
      LEFT JOIN (SELECT  responsavel, COUNT(responsavel) AS pending_tasks
				   FROM  dbo.SinfRegister
				  WHERE  pendente = 1										
			   GROUP BY responsavel) AS dt1
			 ON t.responsavel = dt1.responsavel
      LEFT JOIN (SELECT  responsavel, COUNT(responsavel) AS all_tasks
				   FROM  dbo.SinfRegister								
			   GROUP BY responsavel) AS dt2
			 ON t.responsavel = dt2.responsavel