Solved

# of months between two dates

Posted on 2016-08-02
20
72 Views
Last Modified: 2016-08-22
Dear experts,

I need a simple formula which can calculate the number of months between two dates. I have provided a formula which I picked it up from website and I wish to perfect it to:
consider the holiday if the later date is a holiday, then the formula should consider the day after the holiday and then include it as the month

The list of holidays is provided in sheet 'holidays'

Column F has the desired result.


Kindly help.

Thank you
--of-months-between-two-dates.xlsx
0
Comment
Question by:Excellearner
  • 8
  • 7
  • 5
20 Comments
 
LVL 50

Expert Comment

by:Rgonzo1971
ID: 41739071
Hi,

pls try

=DATEDIF(B9,C9-1,"m")+1

Open in new window

Shouldn't line 5 be 13 Months

Regards
0
 

Author Comment

by:Excellearner
ID: 41739089
Rgonzo, yes it should be 13 and not 12.

Can you please help me understand the logic behind -1 inside the brackets and +1 outside the brackets.

Thank you
0
 
LVL 50

Expert Comment

by:Rgonzo1971
ID: 41739100
we take  may 1, 16 to June 2, 16
that makes
a difference of one month between  may 1, 16 to June 1, 16
plus 1 Equals 2
0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 33

Expert Comment

by:Rob Henson
ID: 41739269
I was trying to take a look but having problems downloading the file.

DATEDIF doesn't take into account holidays.

NETWORKDAYS can take weekends and a list of holidays into account but that gives number of working days rather than months.

Thanks
Rob
0
 
LVL 33

Assisted Solution

by:Rob Henson
Rob Henson earned 250 total points
ID: 41739285
OK, got the file to open.

Formula in D9:

=IF(ISERROR(MATCH(C9,Holidays!A:A,0)),"",C9+1)

Then couple of options for column F:

=ROUNDUP(YEARFRAC(B9,IF(D9="",C9-1,D9-1),1)*12,0)

=DATEDIF(B9,IF(D9="",C9-1,D9-1),"m")+1

Also some questions:
1) What if Start Date is a holiday?
2) What if Finish Date is a holiday and Finish Date +1  is also a holiday?
0
 

Author Comment

by:Excellearner
ID: 41739764
Rob,

Here is the file.
--of-months-between-two-dates.xlsx
0
 
LVL 50

Accepted Solution

by:
Rgonzo1971 earned 250 total points
ID: 41740162
then

pls try
=DATEDIF(B9,D9-(D9-WORKDAY.INTL(D9,-1,MOD(WEEKDAY(D9)+1,7)+1,Holidays!$A$2:$A$20)),"m")+1

Open in new window

--of-months-between-two-datesV1.xlsx
0
 

Author Comment

by:Excellearner
ID: 41740244
Rgonzo,

Can you please explain the logic in the formula. I could not understand it.

Thank you,
0
 
LVL 33

Expert Comment

by:Rob Henson
ID: 41740263
I managed to get the file to download eventually before, hence the formulas which I posted.
0
 

Author Comment

by:Excellearner
ID: 41740333
Rob,

Also some questions:
 1) What if Start Date is a holiday? Very unlikely
 2) What if Finish Date is a holiday and Finish Date +1  is also a holiday? //Then move the date to the next working day but the Month count should still be in the previous month count or in the 1 month count (the floor value for the result)
0
 

Author Comment

by:Excellearner
ID: 41740335
Rob,

The values in column C and D are given I cannot amend those dates
0
 
LVL 50

Expert Comment

by:Rgonzo1971
ID: 41740359
this part
WORKDAY.INTL(D9,-1,MOD(WEEKDAY(D9)+1,7)+1,Holidays!$A$2:$A$20))

Open in new window

calculates the first non holiday date before D9
this part
MOD(WEEKDAY(D9)+1,7)+1

Open in new window

place the weekend after D9 to not affect the calculation of the non holiday date
0
 

Author Comment

by:Excellearner
ID: 41740438
Rob, a correction, sorry for my wrong comment

Values in Col. B and C are given and I cannot change them
Values in Col D are only shown for this illustration to convey my thought process. In the actual file this field would not exist.

Thank you
0
 

Author Comment

by:Excellearner
ID: 41740440
Rgonzo,

The number of months should be calculated based on values in col. b and C and column D would not exist in the actual file.

Kindly help.

Thank you
0
 
LVL 50

Expert Comment

by:Rgonzo1971
ID: 41740442
then my first formula would apply
0
 
LVL 33

Expert Comment

by:Rob Henson
ID: 41740445
Am I right in thinking that you would still have to take into consideration the date in column C could be on the holiday list?
0
 
LVL 50

Expert Comment

by:Rgonzo1971
ID: 41740458
But the author says that the dates are in Col C and they are not adjusted for Holidays
0
 

Author Comment

by:Excellearner
ID: 41740612
Dates in col C are given and they can be coinciding with the list of the dates in the tab 'holidays'.

The idea is to get a formula to do the following:
1. check if the value in tab Examples, col C will coincide with the list in tab Holidays, Col A
2. Then the formula should increment the value in tab Examples, col C by one date
3. Further, the formula should check if the value arrived in step 2 above is working day or a weekend (Saturday or Sunday)
4. If the result of step 4 coincides with weekend, then the formula should increment it by 1 (if sunday)or 2 (if Saturday) to arrive at the next working day Monday.
5. if the result of Step 4 is Monday and a holiday (as per list), then it should increment by 1 day again to result in Tuesday.

Now suppose if as per the default calculation col. c less Col. B results in 2 months,
then by following step 2-5 should also result in 2 months and not 3 months.

Sorry if I have confused the forum and I hope I am clear with my request now.

Kindly help
0
 
LVL 50

Expert Comment

by:Rgonzo1971
ID: 41740624
Hi,

If it does not change the value of the result at the end, why does the formula have to know there is a weekend or a holiday?
0
 
LVL 33

Expert Comment

by:Rob Henson
ID: 41742264
I agree with RGonzo, I think you are not comparing like with like, comparing whole months with individual days or small groups of days.

How can single or multiple holiday days have an impact on the result? For lapsed months the only way that holidays will have an impact is when you assign a whole month as a holiday.

Thanks
Rob
0

Featured Post

Free Tool: SSL Checker

Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This tutorial explains how to create a series of drop-down lists that are dependent upon prior selections to guide (“force”) the user to make the correct selection and reduce data errors within Microsoft Excel. Excel 2010 was used for this tutorial;…
How to get Spreadsheet Compare 2016 working with the 64 bit version of Office 2016
The viewer will learn how to create a normally distributed random variable in Excel, use a normal distribution to simulate the return on an investment over a period of years, Create a Monte Carlo simulation using a normal random variable, and calcul…
Finds all prime numbers in a range requested and places them in a public primes() array. I've demostrated a template size of 30 (2 * 3 * 5) but larger templates can be built such 210  (2 * 3 * 5 * 7) or 2310  (2 * 3 * 5 * 7 * 11). The larger templa…

733 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question