Quantity Balance And Sum

I have following table structure


CREATE TABLE [dbo].[EMPLOYEE] (
[REC_ID] [int] IDENTITY (1, 1) NOT NULL ,
[EMP_ID] [varchar] (50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL ,
[NAME] [varchar] (100) COLLATE SQL_Latin1_General_CP1_CI_AS NULL ,
[PROJECT_ID] [varchar] (10) COLLATE SQL_Latin1_General_CP1_CI_AS NULL ,
[LOGIN_ID] [varchar] (10) COLLATE SQL_Latin1_General_CP1_CI_AS NULL
) ON [PRIMARY]
GO



CREATE TABLE [dbo].[PPE_STOCK] (
[REC_ID] [int] IDENTITY (1, 1) NOT NULL ,
[PPE_ID] [varchar] (50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL ,
[PPE_NAME] [varchar] (50) COLLATE SQL_Latin1_General_CP1_CI_AS NULL ,
[QUANTITY] [int] NULL
) ON [PRIMARY]
GO

CREATE TABLE [dbo].[PPE_ITEM_ISSUE] (
[PII_ID] [int] IDENTITY (1, 1) NOT NULL ,
[EMP_ID] [varchar] (50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL ,
[DATE_REQUEST] [datetime] NULL ,
[QUANTITY_ISSUE] [int] NULL ,
[DATE_ISSUE] [datetime] NULL
) ON [PRIMARY]
GO


I want to calcalate the balance quantity avaiable in the stock.

PPE_STOCK => STOCK OF QUANTITY TABLE
PPE_ITEM_ISSUE => STOCK QUANTITY ISSUE TO EMPLOYEE TABLE

query retrieve like this.

Name....EMP_ID....PPE_NAME,..QUANTITY_ISSUE.Stock Qty.Balance Qty
-----------------------------------------------------------------
Martin..p0012456..Safety Gloves 1 .......100........99
Martin..p0012566..Safety Glass 1 .......100........99
Peter...p00123456.Safety Gloves 1........100........98
Jone....p00987654.Safety Helmet 1........100........99
Khan....p0012122..Safety Helmet 1........100........98
....

stock quanity minus the issue qauantity and retreive balance QTY
how ?

How can calcuate / retrieve the balance quantity by the query ?

Please us query calcuation.

regards
Martin