Crosstab two joined tables multiplies the data in each column ....

Question

below is code that crosstabs monthy sales numbers and totals for each month.  So what I need to do is add a column that totals last years sales (table will be called [2013]) and add a column called 2013 YTD. I also need to add a calculation column that
calculates growth from one year to another. So I join the 2013 table and add one last line that sums 2013 sales but i need only Jan-Mar at this point. in other words I just need to see the total sales for each dealer from 2013 Jan-Mar while still viewing Jan-Dec
for the current year. So looking at the end product I need to see the Dealer Info, Jan, Feb, Mar, Apr......and at the end 2013 Sales and Growth. Thus, the Where clause. Unfortunately, each months sales are multiplied x 3 with or without the 2013 sum line.
As soon as I join the tables the numbers get multiplied.
What am I missing??????
SELECT    
substring([2014].Dealer,18,50)AS
[Dealer Name],substring([2014].Dealer,9,1)AS
[District],substring([2014].Dealer,11,6)AS
[Dealer Code],
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 1 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Jan,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 2 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Feb,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 3 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Mar,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 4 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Apr,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 5 THEN
[2014].[Sales Count]
ELSE 0 END)
AS May,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 6 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Jun,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 7 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Jul,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 8 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Aug,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 9 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Sep,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 10 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Oct,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 11 THEN
[2014].[Sales Count]
ELSE 0 END)
AS Nov,
SUM(CASE
WHEN [2014].[Transaction Sales Month]
= 12 THEN
[2014].[Sales Count]
ELSE 0 END
AS
Dec,
SUM([2014].[Sales Count])
AS [2014 Total],
FROM        
dbo.[2014]
GROUP
BY substring([2014].Dealer,18,50),substring([2014].Dealer,9,1),substring([2014].Dealer,11,6)

Answer 1

This needs to be moved to Transact-SQL forum. You may want to post DDL of your tables, some input data (as insert statements) and desired output.
In the meantime I think you'll find this blog post helpful:
Aggregates with multiple tables
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