title: Excel Macro - combine Multiple Columns Into One
body: <p>I have an excel 2007 worksheet with 12 columns (each column is corresponding to a month) and every column includes +/-30000 rows of daily rainfall data. What I need to do is combine these columns of data into one new column (one continuous rainfall series) as follows:</p>
  
  <ol>
  <li><p>Copy the first 31 (the number of days of January) rows “A1:A31” from column 1 to the new column</p></li>
  <li><p>Copy the first 28 (the number of days of February) rows from column 2 and place it beneath the previous values in the new column, and, etc.…. [The first 31 rows (March) from column 3, 30 from column 4, 31 from column 5, 30 from column 6, 31 from column 7, 31 from column 8, 30 from column 9, 31 from column 10, 30 from column 11 and 31 from column 12] </p></li>
  <li><p>Then, do the same for the next year, i.e. copy the second 31 values “A32:A62” from column 1 and place it beneath the previous year (Step 1 &amp; 2) in the new column.</p></li>
  <li>In total, the result will be a continuous daily rainfall series.</li>
  </ol>
  
  <p>I have tried my best to accomplish this, but I have got nowhere! </p>
  
  <p>Please, could someone help me with this? </p>
  
  <p>Thanks a lot</p>
  
  <p>==================</p>
  
  <h1>More explanation</h1>
  
  <p>The data are sorted into several columns by month, for several years, and it looks something like this: </p>
  
  <p>Year   Day  Jan   Feb   March </p>
  
  <p>1990    1    25   15    </p>
  
  <p>1990    2   20   12    </p>
  
  <p>1990     3   22         </p>
  
  <p>1990      4  26           </p>
  
  <p>So every column has a different length from month to month according to the number of days in each month (e.g., January has 31 days). Now, I need to combine all the entries into one long column. So it would look like this: </p>
  
  <p>25</p>
  
  <p>20</p>
  
  <p>22</p>
  
  <p>26</p>
  
  <p>15</p>
  
  <p>12</p>
  
  <p>Any help would be appreciated!</p>