Today is Friday the 13th. If you are a raging friggatriskaidekaphobiac, I suggest you to stop reading this post. For the rest of you, I have something fun.
Given a year in cell C3, let’s find out all the months with Friday the 13th. Something like this:

[Related: Finding next Friday the 13th using formulas]
Finding all Friday the 13ths in a year
Here is a formula to find the first Friday the 13th in a year.
{=IFERROR(SMALL(IF(WEEKDAY(DATE($C$3,ROW($A$1:$A$12),13))=6,ROW($A$1:$A$12)),1),””)}
Let’s understand how it works, going from inside out:
DATE($C$3,ROW($A$1:$A$12),13) portion: This generates an array of 12 dates, one for each 13th of the month in the year C3.
WEEKDAY(DATE(…))=6 portion: This checks how many of those dates are Fridays. Returns an array of TRUE / FALSE values.
IF(WEEKDAY(DATE(…))=6,ROW($A$1:$A$12)) portion: This returns an array of month numbers where we have Friday the 13th and FALSE values.
SMALL(IF(…),1) portion: This will give us the first month (ie 1st smallest value) with Friday the 13th in the year C3.
IFERROR() to suppress any errors.
To show all the Friday the 13ths in a year, simply replace 1 with an array of numbers (up to 3 should do).
Download Friday the 13th finder workbook
Click here to download Friday the 13th finder workbook. Enter a year in cell C3 and see all the months with Friday the 13th instantly.
A challenge for you…
If you are still reading, I have a challenge for you. Can you write a formula to find the next year with three Friday the 13ths? Assume the year is in C3. Post your formulas / VBA in the comment section.
hint: in the downloadable workbook, you can find an answer for this.
So that’s all for now. Enjoy your Friday the 13th.














11 Responses to “Fix Incorrect Percentages with this Paste-Special Trick”
I've just taught yesterday to a colleague of mine how to convert amounts in local currency into another by pasting special the ROE.
great thing to know !!!
Chandoo - this is such a great trick and helps save time. If you don't use this shortcut, you have to take can create a formula where =(ref cell /100), copy that all the way down, covert it to a percentage and then copy/paste values to the original column. This does it all much faster. Nice job!
I was just asking peers yesterday if anyone know if an easy way to do this, I've been editing each cell and adding a % manually vs setting the cell to Percentage for months and just finally reached my wits end. What perfect timing! Thanks, great tip!
If it's just appearance you care about, another alternative is to use this custom number format:
0"%"
By adding the percent sign in quotes, it gets treated as text and won't do what you warned about here: "You can not just format the cells to % format either, excel shows 23 as 2300% then."
Dear Jon S. You are the reason I love the internet. 3 year old comments making my life easier.
Thank you.
Here is a quicker protocol.
Enter 10000% into the extra cell, copy this cell, select the range you need to convert to percentages, and use paste special > divide. Since the Paste > All option is selected, it not only divides by 10000% (i.e. 100), it also applies the % format to the cells being pasted on.
@Martin: That is another very good use of Divide / Multiply operations.
@Tony, @Jody: Thank you 🙂
@Jon S: Good one...
@Jon... now why didnt I think of that.. Excellent
Thank You so much. it is really helped me.
Big help...Thanks
Thanks. That really saved me a lot of time!
Is Show Formulas is turned on in the Formula Ribbon, it will stay in decimal form until that is turned off. Drove me batty for an hour until I just figured it out.