Today, let’s travel in time. Pack your photon ray guns, extra underwear, buckle your seat belts and open Excel!
Of course, we are not going to travel in time. (Come to think of it, we are going to travel in time. By the time you finish reading this, you would have traveled a few minutes)
We are going to learn how to travel in time when using Excel. In simple terms, you are going to learn how to move forward or backward in time using Excel formulas.
So are you ready to hit the warp speed? Let’s beam up our Excel time machine.
Tip 0 – Date & Time are an illusion
Most important tip for Excel time travelers is to understand that Excel dates & times are just numbers. So when you see a date like 17-October-2013 in a cell, you can safely assume that it is a number disguised to look like 17th of October, 2013. To see the number behind this, just select the cell and format it as number (from Home ribbon).
Now that you understood this concept, let’s jump in to the 42 tips. All these tips assume a date or time value is in the cell A1.
Staying at present:
- To have latest star date in a cell, just press CTRL+; (of course, in Excel world, star date is nothing but whatever date your computer shows)
- To have current time in a cell, just press CTRL+:
- Of course, we time travelers are lazy. So pressing CTRL+; every day or CTRL+: every second is not cool. That is why you can use =TODAY() in a cell to get today’s date. It will automatically change when you re-open the file tomorrow.
- Likewise, use =NOW() to get current date & time in a cell. Remember, although time changes every second, you will not see the cell updated unless the formula is somehow re-calculated. This is done by,
- Pressing F9
- Saving / re-opening the file
- Making any changes to any cell (like typing a value, changing a value)
- Editing the formula cell and pressing Enter
- To check if today is after or before the date in cell A1, you can use =TODAY() > A1. This will be TRUE if A1 has a past date and FALSE if A1 has a future date.
- To know how many days are there between TODAY and the date in A1, use =TODAY() – A1. This will be a negative number if A1 is a future date. To see just the number of days (without negative sign), you can use =ABS(TODAY()-A1)
- To know how many hours are left between the time in A1 and current time, use =(NOW()-A1)*24.
- While the above formula works, it shows hours and fraction. To just see hours and minutes left, you can use =TEXT((NOW()-A1), “[hh]:mm”). Note: This formula works only when A1 < NOW().
- To know how many weeks are left between TODAY() date and a future date in A1, use =(TODAY() –
A1)/7 - To know how many months are left between TODAY() and date in A1, use = DATEDIF(TODAY(), A1, “m”).
Related: How to use DATEDIF function. - To know which month is running, use =MONTH(TODAY())
- To see the month name instead of number, use =TEXT(TODAY(), “MMMM”). This shows the month’s name in your Excel language.
- To know which year is running, use =YEAR(TODAY())
- To see the last 2 digits of the year, you can use =RIGHT(YEAR(TODAY()), 2)
- To find the day of week for TODAY, use =WEEKDAY(TODAY()). This will give a number (1 to 7, 1 for Sunday, 7 for Saturday).
- To see the weekday name instead of number, use =TEXT(TODAY(), “DDDD”).
- To see today’s date alone, use =DAY(TODAY())
- To know if the present year is a leap year or not, see this.
Going back in time
- To go back by 6 days from the date in A1, use =A1-6
- To go back to last Friday use =A1-WEEKDAY(A1, 16). This works in Excel 2010, 2013. If your time machine is old (ie you have Excel 2003 or earlier versions), you can use =A1-CHOOSE(WEEKDAY(A1), 2,3,4,5,6,7,1)
- To go back by 5 weeks, use =A1-5*7
- To go back to start of the month, use =DATE(YEAR(A1), MONTH(A1),1)
- To go back to end of previous month, use = DATE(YEAR(A1), MONTH(A1),1) – 1
- Or use =EOMONTH(A1,-1)
- To go back by 2 months, use =EDATE(A1, -2)
- To go back by 27 working days, use =WORKDAY(A1, -27). This assumes, Monday to Friday as working days.
- To go back by 27 working days, assuming you follow Monday to Friday work week and a set of extra holidays, use =WORKDAY(A1, -27, LIST_OF_HOLIDAYS)
- To go back by 7 quarters, use =EDATE(A1, -7 * 3)
- To go back to the start of the year, =DATE(YEAR(A1), 1,1)
- To go back to same date last year, = DATE(YEAR(A1)-1, MONTH(A1), DAY(A1))
- To go back a decade, =DATE(YEAR(A1)-10, MONTH(A1), DAY(A1))
Going forward in time
We, time travelers are smart people. Once you know that turning the knob backwards takes you to past, you know how to go to future. So I am giving very few examples for going forward in time.
- To go to the 17th working day from date A1, assuming you use Sunday to Thursday workweek, use =WORKDAY.INTL(A1,17,7). This formula works in Excel 2010 or above.
- To go to next hour, use=A1+1/24
- To go to next day morning 9AM, use =INT(A1+1) + 9/24
- To go to 18th of next month, use =DATE(YEAR(A1), MONTH(A1)+1, 18)
- To go to end of the current quarter for date in A1, use =DATE(YEAR(A1), CHOOSE(MONTH(A1), 4,4,4,7,7,7,10,10,10,13,13,13),1)-1
- To go to a future date that is 4 years, 6 months, 7 days away from A1, use =DATE(YEAR(A1)+4, MONTH(A1)+6, DAY(A1)+7)
Finding the amount of time traveled
- To know how many days are between 2 dates (in A1 & A2), use =A1-A2
- To know how many working days are between 2 dates, use =NETWORKDAYS(A1, A2) (remember: A1 should be less than A2).
Fixes for common time travel hiccups
- If you see ###### instead of a date in a cell, try making the column wider. If you still see ######, that means the date value is not understandable by Excel (negative numbers, dates prior to 1st of January 1900 etc.)
- Often when pasting date values in to Excel, you notice that they are not treated as dates. Use these techniques to fix.
- If you pass in-correct values or use wrong parameters, your date formulas show an error like #NUM or #VALUE. Read this to understand how to fix such errors.
Quiz time for time travelers
I see that you safely made it here. I hope you had a good journey. Let me see how good your time traveling is. Answer these questions:
- Write a formula to take date in A1 to next month’s first Monday.
- Given a date in A1, find out the closest Christmas date to it.
Building your own time machine? Check out these tips too
If you work with date & time values often, then learning about them certainly pays off. Read below articles to one up your time travel awesomeness.
- Using Date & Time in Excel
- How to calculate common holiday dates in Excel?
- How to calculate payroll dates?
- How to sort a bunch of birth dates by birthday?
- Check if two dates are in same month
Good luck time traveling. I will see you again in future 🙂
PS: Make sure you attempt the challenges and post your answers in comments.
12 Responses to “Speeding up & Optimizing Excel – Tips for Charting & Formatting [Speedy Spreadsheet Week]”
Usually when I dump data into my files to update values, the formatting sometimes go to all rows or columns. So what I typically will do is go to the last row and then the last column and use Ctrl + Shift + end and then delete the cells highlighted. this will remove all unknown formats in the worksheet. Also, after you have done this, you won't see the benefit until you save the document. Sometimes I even have to close and reopen. The direct sign that this has improved is the size of the scroll bar and range.
I have some comments on a couple of the points.
1. Camera objects
Tip: I use defined names in conjunction with camera tool objects.
Each camera object gets a name like so:
CameraItem01
Referring to: =IF(PicsOn=1,Sheet1!$C$2:$S$5,"")
By setting the PicsOn name to 1, the camera objects become "live", by setting the PicsOn name to 0, they become static. That improves performance enormously.
4: Conditional formatting
Lots of CF rules can slow down your workbook a lot. And it does not show the calc progress a "normal" recalc does on slow workbooks.
5. Format whole columns/rows
as far as I know, there is no problem with formatting entire columns/rows performance-wise, on the contrary, Excel is more efficient when you format an entire column than when you format a couple of 100 rows of a column.
6. Styles.
Here I wholeheartedly disagree. I say: Use styles. And use them religously.
I mean: if you have applied a (custom) style and you need to change a small piece of formatting to make that one cell look right, force yourself to create a new style just for that cell. It forces you to really think about your spreadsheet design and try and streamline it. It also makes it much, much easier to change your sheet's appearance later on. See http://www.jkp-ads.com/articles/styles00.asp
Very good insights Jan..
Camera objects: I often use similar technique to turn off images in my dashboards.
Formats: Thanks for clearing this. Do you think formatting larger ranges has any impact on macro speeds or it does not matter?
Styles: Thanks for telling us about this. As I mentioned, I am not sure about the styles, but I am under the impressions that excessive use of styles can bloat the file size.
@Chandoo:
If you stick to formatting entire rows/columns I don't expect macro speed is affected. Better: try it!
If you use styles properly AND as a replacement of ad-hoc cell formatting, I expect you'll see that the file actually is smaller in size.
This is because the cells now only have a reference to a single style instead of a reference to a custom cell formatting style.
Many cell formatting combinations get created if you format your cells in an ad-hoc manner, which was responsible for the dreaded "Too many different cell formats" error in Excel 2003 and older. Excel 2007 and 2010 have a higher limit there, but it does slow down your file with many of them.
Style bloat in my point of view is what you get by copying and pasting a lot from various other files and thus get Normal 1, Normal 1 1, Normal 1 1 1, ... I have seen workbooks with as many as 6000 styles, all caused by copying and pasting from various differently formatted workbooks.
Excel 2007 and 2010 have fixed a number of issues regarding copying of styles, but for workbooks with a long editing history, the trouble is already in the workbooks.
Cant emphasise the importance of reducing the amount of formatting in a workbook - this has a suprising impact on workbook size. I've always kept to one font, and no more than three colours - this has worked well for me. Keeping things clean and simple should be the motto when designing any type of report/dashboard that is going to be distributed around the organisation.
You can also save a few MB's by saving as an xlsb file.
Has anyone else mentioned that only the first item in the "more ..." section is hyperlinked.
Prem, have you confirmed by trial that XLSB file size is smaller than same XLSX file? Sorry, I just tried it with a small, simple XLSM file. I was surprised to see you are correct. File went from 40kb to 37kb. I thought that the compression of the new file would make the new file smaller.
@Ron
All Excel files have a minimum overhead that they have to include which is around 8KB, just to store a simple number or letter.
So with a small file of 40KB you will not see a huge improvement in file size
With files greater than 10MB you will see large improvements in size.
The compression gained also depends on what the contents of the file include. That is straight numbers, text and formulas can be greatly compressed whereas files that contain a lot of objects especially pictures gain very little from using *.xlsb files.
@Ron.. the other articles are yet to be published. All the links will be updated by Tuesday (27th March).
Hi,
I have a need for x,y scatter chart to have arround 30 data series.
like this:
http://i65.tinypic.com/jra8lc.jpg
Also I have multiple of such charts in one excel file.
Is there any way to make excel faster, because it is irritatingly slow?
(though my PC config. is quite on the level)
Thanks in advance!!!
@Mil
30 series won't be the issue
It is the number of points in the series
Also remove all fancy modifications, like shadows, fancy fills etc
I'd suggest asking the question in the Chandoo.org Forums http://forum.chandoo.org/
Attach a sample file with an example of what you are after
@Hui
I've already removed all fancy mod. The problem is there are also a lot of data points in one series.
Thanks for the advice!
@Mil
Do you really need every data point ?
Where is the chart being presented Screen or Report
On a screen you are unlikely to use more than 800 pixels for the chart area
So using any more than about 250 points is not adding values
On an A4 chart in landscape lets say the chart area is 6" long and at 300dpi that is 2000 pixels
Once again using more than 800-1000 points will not add any value
I have seen charts with 30,000+ points and when this is explained and a work around shown people appreciate the speed up
For a work around try setting up an area where you select say every x'th point using an Offset or Index Function
Then plot that data
I'd suggest asking the question in the Chandoo.org Forums http://forum.chandoo.org/
Attach a sample file with an example of what you are after