Although my sheets are named Jan-Dec, would I still use the number sequence above?
Also what does the "29" and "mmm" refer to
=TEXT({1,2,3,4,5,6,7,8,9,10,11,12}*29,"mmm")
That generates an array of the month names (your sheet names) in the short name format mmm. January = Jan
Try this experiment...
Enter this formula in cell A1 and copy down to A12:
=ROW()*29
Now, enter this formula in B1 and copy down to B12:
=TEXT(A1,"mmm")
What you see in B1:B12 is the same thing that this formula is doing:
=TEXT({1,2,3,4,5,6,7,8,9,10,11,12}*29,"mmm")
How does this work?
In Excel Dates are really just numbers formatted to look like dates.
Those numbers are the count of days starting from a base date. The default base date is Jan 1 1900. Jan 1 1900 has the numeric value of 1. Each successive day the count increases by 1 like this:
Jan 1 1900 = 1
Jan 2 1900 = 2
Jan 3 1900 = 3
Jan 4 1900 = 4
Jan 5 1900 = 5
Mar 1 1975 = 27454
Apr 6 2011 = 40639
These numbers are known as the date serial numbers.
Now, look at the numbers in A1:A12
Book1 |
---|
|
---|
| A |
---|
1 | 29 |
---|
2 | 58 |
---|
3 | 87 |
---|
4 | 116 |
---|
5 | 145 |
---|
6 | 174 |
---|
7 | 203 |
---|
8 | 232 |
---|
9 | 261 |
---|
10 | 290 |
---|
11 | 319 |
---|
12 | 348 |
---|
|
---|
29 = date serial number for Jan 29 1900
58 = date serial number for Feb 27 1900
87 = date serial number for Mar 27 1900
116 = date serial number for Apr 25 1900
145 = date serial number for May 24 1900
174 = date serial number for Jun 22 1900
203 = date serial number for Jul 21 1900
232 = date serial number for Aug 19 1900
261 = date serial number for Sep 17 1900
290 = date serial number for Oct 16 1900
319 = date serial number for Nov 14 1900
348 = date serial number for Dec 13 1900
If you need visual proof of those dates and number values then select the range A1:A12 and format Date.
So, the TEXT function takes the date serial number and returns its corresponding month name:
=TEXT(29,"mmm") = Jan
=TEXT(58,"mmm") = Feb
=TEXT(87,"mmm") = Mar
=TEXT(116,"mmm") = Apr
=TEXT(145,"mmm") = May
=TEXT(174,"mmm") = Jun
=TEXT(203,"mmm") = Jul
=TEXT(232,"mmm") = Aug
=TEXT(261,"mmm") = Sep
=TEXT(290,"mmm") = Oct
=TEXT(319,"mmm") = Nov
=TEXT(348,"mmm") = Dec