Why Azure SQL Server table used space is too high?

I have two tables in my SQLServer database (azure managed), and the structure of two tables as below (for easy reference renamed them) **dbo.TABLE1** CREATE TABLE [dbo].[TABLE1] ( [ID] VARCHAR (50) NOT NULL, -- PK index [S_NUMBER] VARCHAR (50) NOT NULL, [MAKE] VARCHAR (12) NULL, [MODEL] VARCHAR (40) NULL, [C_ID] VARCHAR (50) NOT NULL, [C_CODE] REAL NULL, [C_DESCRIPTION] VARCHAR (50) NULL, [S_CODE] REAL NULL, [S_DESCRIPTION] VARCHAR (50) NULL, [LS_TIME] DATETIME2 (7) NOT NULL, [LE_TIME] DATETIME2 (7) NOT NULL, [YEAR] DATE NULL, [MONTH] DATE NULL, [WEEK] DATE NULL, [DAY] DATE NULL, [HOUR] DATETIME2 (7) NULL, [WEEK_DAY] VARCHAR (12) NULL, [F_USED] REAL NULL, [F_USED_UOM] VARCHAR (12) NULL, [DIST_TRAVE] REAL NULL, [DIST_TRAV_UOM] VARCHAR (12) NULL, [DURATION] REAL NULL, [DURATION_UOM] VARCHAR (12) NULL, [WEIGHT_MOVED] REAL NULL, [WEIGHT_STORED] REAL NULL, [WEIGHT_UOM] VARCHAR (12) NULL, [CREATED_TIME] DATETIME NULL, [MODIFIED_TIME] DATETIME NULL, [OPER_ID] VARCHAR (12) NULL, [OPER_TYPE] VARCHAR (12) NULL, [START_TIME] DATETIME2 (7) NULL, [END_TIME] DATETIME2 (7) NULL, [UTC_DAY] DATE NULL, [UTC_WEEK] DATE NULL, [UTC_MONTH] DATE NULL, [UTC_YEAR] SMALLINT NULL, [UTC_HOUR] TINYINT NULL, [LOCAL_HOUR] TINYINT NULL, [EFFICIENCY] DECIMAL (5) NULL, [JS_ID] BIGINT NOT NULL, [L_ZONE] NVARCHAR (50) NULL, [D_ZONE] NVARCHAR (50) NULL, [SHIFT_TYPE] NVARCHAR (12) NULL, [SHIFT_DATE] DATE NULL, [D_CATEGORY] NVARCHAR (50) NULL, [REC_CATEGORY] NVARCHAR (12) NULL, [LSERIAL_NUMBER] VARCHAR (50) NULL, [GPS_TIME] DATETIME NULL, [GPS_STATUS] VARCHAR (12) NULL, [A_ID] VARCHAR (50) NULL, [E_ID] VARCHAR (50) NULL, [TAG_GUID] VARCHAR (64) NULL, [LZ_ID] VARCHAR (64) NULL, [DZ_ID] VARCHAR (64) NULL, [LZ_VERSION] INT NULL, [DZ_VERSION] INT NULL, [Z_ID] BIGINT NULL, [SHIFT_ID] NVARCHAR (64) NULL, [LI_TIME] DATETIME2 (3) CONSTRAINT [S_CREATED_TIMESTAMP] DEFAULT (sysdatetime()) NULL, [PC_ID] INT NOT NULL DEFAULT 0, [L_MAKE] VARCHAR (32) NULL, [TV_MOVED] DECIMAL (18, 2) NULL ); **dbo.TABLE2** CREATE TABLE [dbo].[TABLE2]( [ID] NVARCHAR(32) NOT NULL, -- PK index [C_ID] NVARCHAR(64), [DURATION] DECIMAL(18,2), [P_COUNT] BIGINT, [LS_TIME] DATETIME, [LE_TIME] DATETIME, [S_AGG_ID] NVARCHAR(32) -- FK index ) **dbo.TABLE2** is subset of **dbo.TABLE1** with only 5 columns, and the row count is same. We capture only 5 columns from **dbo.TABLE1** and insert in **dbo.TABLE2**. But the size(space used) of **dbo.TABLE2** is almost **3 times** the **dbo.TABLE1**. **Indexes:** Apart from **PK**, **FK** indexes we have one additional index on **dbo.TABLE1** with include columns [JS_ID, MAKE, S_NUMBER, TAG_GUID, LE_TIME] Why the space used is too high for smaller table even though row count is same as its source table?