Please Note: This article is written for users of the following Microsoft Excel versions: 2007, 2010, 2013, and 2016. If you are using an earlier version (Excel 2003 or earlier), this tip may not work for you. For a version of this tip written specifically for earlier versions of Excel, click here: Tombstone Date Math.

Tombstone Date Math

by Allen Wyatt
(last updated May 20, 2017)

2

Robert loves to work on genealogy. Sometimes when he finds an older cemetery, instead of the birth and death dates being visible on a tombstone, just one date is visible and an age. For example, "born: Jan 18, 1801, died 81 yrs, 11 mths, 17 days" or "age: 93 yrs, 8 mths, 22 days, died March 18, 1901." Robert is wondering if there is any way to calculate the missing date to the day.

There is a way to do this, but it doesn't involve the use of regular worksheet functions. While Excel includes a rich assortment of worksheet functions that allow you to manipulate dates, the "basis date" for Excel is January 1, 1900; this is the date from which all dates are calculated. (You can change the basis date, but only by four years, to 1904. This capability is provided for compatibility with Excel on the Mac.) This means that older dates—such as those you would find in the cemetery for genealogy purposes—can't be directly calculated in Excel.

Fortunately, VBA doesn't have this limitation. This means that you can easily create a user-defined function (a macro) that will do the math for you. Start by placing the starting date (either birth or death date) in cell B1. Then, in cells B2:B4 enter the number of years, months, and days by which you want to adjust the starting date. Thus, if B1 contains a birth date, then cells B2:B4 should be positive (you want to add them to the starting date). If B1 contains a death date, then B2:B4 should be negative (you want to subtract them from the starting date).

Then, create this macro:

Function FindDate(Start As Date, iYrs As Integer, _
  iMths As Integer, iDays As Integer)

    Application.Volatile
    Dim D As Date

    D = DateAdd("yyyy", iYrs, Start)
    D = DateAdd("m", iMths, D)
    D = DateAdd("d", iDays, D)

    FindDate = Format(D, "m/d/yyyy")
End Function

In whatever cell you want to display the calculated date you can enter the following formula:

=FindDate(B1,B2,B3,B4)

The result of the function is a formatted date that represents the start date adjusted by the years, months, and days you specify. So if cell B1 contains 1/18/1801, cell B2 contains 81, cell B3 contains 11, and cell B4 contains 17, then the function will return 1/4/1883. Similarly, if cell B1 contains 3/18/1901, cell B2 contains -93, cell B3 contains -8, and cell B4 contains -22, then the result returned will be 6/26/1807.

Note:

If you would like to know how to use the macros described on this page (or on any other page on the ExcelTips sites), I've prepared a special page that includes helpful information. Click here to open that special page in a new browser tab.

ExcelTips is your source for cost-effective Microsoft Excel training. This tip (12277) applies to Microsoft Excel 2007, 2010, 2013, and 2016. You can find a version of this tip for the older menu interface of Excel here: Tombstone Date Math.

Author Bio

Allen Wyatt

With more than 50 non-fiction books and numerous magazine articles to his credit, Allen Wyatt is an internationally recognized author. He is president of Sharon Parq Associates, a computer and publishing services company. ...

MORE FROM ALLEN

Disappearing Macro Menus

Word is quite versatile in how you can customize it. You can add all sorts of macros to menus, but doing so may cause ...

Discover More

Conditional Formatting

One of the powerful features of Excel is the ability to format a cell based on the contents of that cell or another. It ...

Discover More

Previewing Your Files

Want to get a glimpse of what is inside a file without evening opening it? Drive provides two distinct ways of peeking ...

Discover More

Program Successfully in Excel! John Walkenbach's name is synonymous with excellence in deciphering complex technical topics. With this comprehensive guide, "Mr. Spreadsheet" shows how to maximize your Excel experience using professional spreadsheet application development tips from his own personal bookshelf. Check out Excel 2013 Power Programming with VBA today!

More ExcelTips (ribbon)

End-of-Month Calculations

Don't want to use the EOMONTH function to figure out the end of a given month? Here are some other ideas for discovering ...

Discover More

Determining Month Names for a Range of Dates

Given a starting date and an ending date, you may want to generate the names of all the months between those two dates. ...

Discover More

Ages in Years and Months

Calculating an age is a common task when working with dates. If you want to figure out the number of years and months ...

Discover More
Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

View most recent newsletter.

Comments

If you would like to add an image to your comment (not an avatar, but an image to help in making the point of your comment), include the characters [{fig}] in your comment text. You’ll be prompted to upload your image when you submit the comment. Maximum image size is 6Mpixels. Images larger than 600px wide or 1000px tall will be reduced. Up to three images may be included in a comment. All images are subject to review. Commenting privileges may be curtailed if inappropriate images are posted.

What is two minus 1?

2017-06-24 23:57:14

Clive

Your readers need to be careful if they are working with dates either side of February 1900. We all know that centuries (1800, 1900 etc) are not leap years. But Excel for Windows shows 29 days in Feb 1900. So 2 months after the Microsoft date system began it is wrong!
I assume that is why Apple chose to start in 1904 and bypass this problem.


2017-05-20 10:10:50

Brian Lair

Great tip! Very useful for us amateur genealogists. Thanks!


This Site

Got a version of Excel that uses the ribbon interface (Excel 2007 or later)? This site is for you! If you use an earlier version of Excel, visit our ExcelTips site focusing on the menu interface.

Newest Tips
Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

(Your e-mail address is not shared with anyone, ever.)

View the most recent newsletter.