Restructuring massive excel document - excel

Question

I have a task to restructure a two column excel sheet and expand it. Here is a picture to show what needs to be done, the data on the left of the green column is the original data and the data on the right is how it should look, but its only done for the first entry, I need to replicate it for all 10,000 rows of data.
To explain more indepth, each CRD it needs to be expanded to 160 rows, and go from 1978->2018 while listing the quarters out for each year. What is the best approach? Is it possible to write a macro to solve this ?

Answer 1

The following expects Sheet1 ans Sheet2 to be the names. And goes for 158 quarters.
Option Explicit
Sub doFromThru()
' clear contents
Sheets("Sheet2").Select
Cells.Select
Selection.ClearContents
Range("A1").Select
Cells(1, "A") = "CRD"
Cells(1, "B") = "Year"
Cells(1, "C") = "Quarter"
Cells(1, "D") = "QuarterNumerical"
Cells(1, "E") = "Disclosure"
Dim nOutRow As Integer
nOutRow = 1
' step thru all the rows on the input sheet
Dim nInRow As Long, maxInRow As Long, nInCRD As String, nInDisc As String
maxInRow = Sheets("Sheet1").Cells(Rows.Count, "A").End(xlUp).Row
For nInRow = 2 To maxInRow
nInCRD = Sheets("Sheet1").Cells(nInRow, "A")
nInDisc = Sheets("Sheet1").Cells(nInRow, "L")
' create the new rows on Sheet2
Dim dFrom As String, nQtr As Integer
dFrom = DateValue("Oct 1978") ' starting from here
For nQtr = 1 To 158
nOutRow = nOutRow + 1
Sheets("Sheet2").Cells(nOutRow, "A") = nInCRD
Sheets("Sheet2").Cells(nOutRow, "B") = Format$(dFrom, "yyyy")
Sheets("Sheet2").Cells(nOutRow, "C") = Format$(dFrom, "Q")
Sheets("Sheet2").Cells(nOutRow, "D") = nQtr
Sheets("Sheet2").Cells(nOutRow, "E") = nInDisc
dFrom = DateAdd("Q", 1, dFrom)
Next nQtr
Next nInRow
End Sub
Add some diagnostics to tell you more. After nOutRow = nOutRow + 1
Sheets("Sheet2").Cells(1, "G") = nInRow
Sheets("Sheet2").Cells(1, "H") = nOutRow
Sheets("Sheet2").Cells(1, "I") = nQtr
Sheets("Sheet2").Cells(1, "J") = nInDisc

Answer 2

Untested.
Code assumes you want to start from Q4 of the year 1978 and will loop
for 159 quarters after 1978 Q4. (If necessary, you can change this by changing the value of TOTAL_QUARTERS and START_QUARTER in the code)
You will need to change "Sheet1" in the code to whatever the name of your sheet is.
Code tries to overwrite the contents of columns CH to CL on said sheet. So you might want to save a copy of your workbook before running.
Code:
Option Explicit
Sub ExpandRows()
Const START_YEAR as long = 1978
Const START_QUARTER as long = 4
Const TOTAL_QUARTERS as long = 160
With thisworkbook.worksheets("Sheet1")
Dim lastRow as long
lastRow = .cells(.rows.count, "A").row
Dim inputCRD() as variant
inputCRD = .range("A2:A" & lastRow).value2
Dim inputDisclosure() as variant
inputDisclosure = .range("L2:L" & lastRow).value2
Dim yearOffset as long
Dim quarterIndex as long
Dim numericalQuarterIndex as long
Dim totalRowCount as long
totalRowCount = (lastRow - 1) * TOTAL_QUARTERS ' -1 to skip first row
Dim outputArray() as variant
Redim outputArray(1 to totalRowCount, 1 to 5)
Dim readIndex as long
Dim writeIndex as long
For readIndex = lbound(inputCRD,1) to ubound (inputCRD,1)
quarterIndex = START_QUARTER
For numericalQuarterIndex = 1 to TOTAL_QUARTERS
writeIndex = writeIndex + 1
outputArray(writeIndex, 1) = inputCRD(readIndex, 1)
outputArray(writeIndex, 2) = START_YEAR + yearOffset
outputArray(writeIndex, 3) = quarterIndex
outputArray(writeIndex, 4) = numericalQuarterIndex
outputArray(writeIndex, 5) = inputDisclosure(readIndex, 1)
If quarterIndex < 4 then
quarterIndex = quarterIndex + 1
Else
yearOffset = yearOffset + 1
quarterIndex = 1
End if
Next numericalQuarterIndex
Next readIndex
.range("CH2").resize(ubound(outputArray,1), ubound(outputArray,2)).value2 = outputArray
End with
End sub