Multiple rows of horizontal data needing to arrange vertically (stacked)

I have 500 rows with 6 columns of data (colunms D:I) in each row that need to be arranged vertically on top of each other with the first three columns (Columns A:C) remaining constant using cell references. I realize this will be three separate equations. Please help...Thank You


SEE ATTACHED SHEET

Current Data Set:

A B C D E F G H I
1 Invoice Date Company Invoice # Account 1 Account 2 Account 3 Account 4 Account 5 Account 6
2 1/1/12 Vendor 1 987 $1.00 $2.00 $3.00 $4.00 $5.00 $6.00
3 1/2/12 Vendor 2 654 $7.00 $8.00 $9.00 $10.00 $11.00 $12.00
4 1/3/12 Vendor 3 321 $13.00 $14.00 $15.00 $16.00 $17.00 $18.00
etc
etc
etc

Needs to be arranged as follows:

1 Invoice Date Company Invoice # Amount Account
2 1/1/12 Vendor 1 987 $1.00 acc1
3 1/1/12 Vendor 1 987 $2.00 acc2
4 1/1/12 Vendor 1 987 $3.00 acc3
5 1/1/12 Vendor 1 987 $4.00 acc4
6 1/1/12 Vendor 1 987 $5.00 acc5
7 1/1/12 Vendor 1 987 $6.00 acc1
8 1/2/12 Vendor 2 654 $7.00 acc2
9 1/2/12 Vendor 2 654 $8.00 acc3
10 1/2/12 Vendor 2 654 $9.00 acc4
11 1/2/12 Vendor 2 654 $10.00 acc5
12 1/2/12 Vendor 2 654 $11.00 acc6
13 1/2/12 Vendor 2 654 $12.00 acc7

A, B, & C

Thank you

there is 3 kinds formula

first write at A18
=INDEX(A$3:A$7;TRUNC((ROW(1:1)-1)/6)+1)
copy it to column B&C then copy down

second at D18 (amount)
=INDEX($D$3:$I$7;MATCH(B18;$B$3:$B$7;0);COUNTIF(B$18:B18;B18))
copy down

third at E18 (account)
=INDEX($D$2:$I$2;COUNTIF(B$18:B18;B18))
copy down

Copy range-----> paste special [transpose]