Formula help for a date function

[mjmoon]

I need a formula that will calculate the next review date based on the original date plus 180 days. The next review date is always going to the first day of a month regardless if the orginal date was on the 12th or 28th as an example. The problem I have is the original date can be from 3 to 6 years ago, each one is different. This spreadsheet is used once a month on the first day.

I have cell C3 set for the user to put in the first day of the particular month they are working on. I beleive this has to be part of the formula some way or form.

Column B contains the original date of the document needing to be reviewed. Column C is where I want it to calucate the next review date based on the above mentioned condition of 180 days from the original date. Here is what I want column C to look like with the new formula.

Original Date = 5-18-09 next review date = 11-1-10
Original Date = 6-29-09 next reveiw date = 12-1-10
Original Date = 5-27-10 next reveiw date = 11-1-10

The next review dates will have to stay the same each month until the date exceeds what is in C3 then it will need to calucate the next 180 reveiw date.

Thank you in advance for your consideration.

 

[Special-K99]

Try this

=A1+180-(DAY(A1+180)-1)

where A1 is the start date

 

[mjmoon]

Thanks for the quick reply. The formula doesn't quit work. With this formula scenario #1 returned 11-1-09 when it should be 11-1-10. Scenario #2 should be 12-1-10. Scenario #3 is correct because the original date is less than 180 days old where #1 is actually 435 days old based on the original date to today's date. Any other suggestions?

 

[Special-K99]

You say "the next review date based on the original date plus 180 days"

but 05-18-2009 + 180 days is not 11-01-2010 ?

Would it be right to say the review date is obtained by

1) calculate review date + 180 days
2) Take the result of that date and calculate the first of that month
3) Regardless of the result of that year change the year to 2010

?

 

[sumuwin]

Hi

assuming your date is in cell A1, how about

For 6 months

=DATE(YEAR(NOW()),MONTH(A1)+6,1)

For 180 days

=DATE(YEAR(NOW()),MONTH(A1),1)+180

atb
sumuwin

 

[Special-K99]

Try

=DATEVALUE(MONTH(A1+180)&"01-2010")

 

[barry houdini]

Let's suppose one of your dates is 13th April 2008, presumably the next review is 1st Oct 2010, when does that change? Assuming that it should change to 1st April 2011 once C3 reaches 1st Oct 2010 try

=EOMONTH(B1,CEILING(DATEDIF(B1-DAY(B1)+1,C3,"m")+1,6)-1)+1

 

[mjmoon]

First of all, I apologize for not wording my question correctly, my fault. Thanks to all for your input. I ended up using Barry's formula and everything worked great! Thank you again. I can't say enough how valuable this resource is and do appreciate everybodys time they put into answering these post.