“Start with a joke.” My boss used to say when I am nervous about an upcoming presentation. Although, I am not nervous to post this article, I think a joke will always help.
So here it goes:
[originally posted on 5th May 2008]
Now to more serious matters.
VLOOKUP (and other lookup formulas) are very powerful and quite practical. They can fetch you the information you are looking for from a heap of data.
Now that we have seen the power of VLOOKUP thru several posts this week, I want to test your understanding of these formulas by presenting 3 challenges.
Download the excel workbook with these challenges
Click here to download excel workbook with all the data for these challenges.
Challenge # 1: Price After Discount
We come across this problem quite often. You have a list of discount codes and applicable quantity thresholds. For eg. you may sell an item at $50, but if I buy more than 1 item, you will give a 10% discount. The discount goes up as I purchase more quantity.
Now, given a list of item quantities, how do you calculate the amount payable using lookup formulas? That is our first challenge.
Challenge # 2: Price after accumulated quantity discount
This is essentially same as above formula, but the discounts apply on accumulated quantities bought so far. For eg. I will get first item for 0% discount, 2nd and 3rd items for 10% discount, 4th item for 15% discount … 26th item for 50% discount etc.
Now, given a list of customer names and quantities they bought (in the same order), how do you calculate the amount payable for each transaction?
Challenge # 3: Closest price based on the quantity purchased
This is an interesting challenge. The price after discount is determined based on the quantity bought. For eg. the discount thresholds are 1, 3, 5, 10, 25 etc. Now, given a quantity of items bought, we determine the price by finding the closest threshold to it. So, a quantity of 7 will get the price from threshold 5 as against 10.
Few guidelines on solving these challenges:
Although the above problem might appear simple, the solution is not so straightforward.
- Use a variety of formulas: Do not just rely VLOOKUP. Instead experiment with formulas like SUMIF, COUNTIF, INDEX, MATCH etc. to get results
- Use helper columns: Break down the problem in to several steps and use helper columns to get the results
- Use pen & paper: Write down the logic first, then simulate it in excel using formulas. It clears your mind fast.
- Many solutions exist: Each problem can be solved in several different ways. So once you find a solution, feel free to explore other options
- Share your solutions: Use comments box to share your solutions with us. I am always looking for new ways to solve problems. So teach me…
Solution to the Challenges:
Here is a workbook with one set of solutions for the problems. As I said, many other solutions do exist. So use this workbook as an indication of what is possible.
Click here to download excel workbook with all the data for these challenges.
One Link to More VLOOKUP Awesomeness:
Debra at Contextures has chipped in with some interesting videos on VLOOKUP formulas. Check them out here.
The 2nd Joke:
It is quite difficult to set an expectation and then meet it. More so with jokes. But do you know that Chandoo.org’s 404 pages show Excel error messages? For example go to http://chandoo.org/wp/missing_file/. Refresh the page to see a different message. 🙂
It is Diwali (the festival of lights) in India this weekend. So I am going to spend time with family, light some fireworks and relax. I wish you a happy Diwali if you celebrate one. Even otherwise, I wish a lot of light and warmth in to your life this year.
12 Responses to “29 Excel Formula Tips for all Occasions [and proof that PHD readers truly rock]”
Some great contributions here.
Gotta love the Friday 13th formula 😀
Great tips from you all! Thanks a lot for sharing! bsamson, particularly you helped me on a terribly annoying task. 🙂
(BTW, Chandoo, it's not exactly "Find if a range is normally distributed" what my suggestion does. It checks if two proportions are statistically different. I probably gave you a bad explanation on twitter, but it'd be probably better if you fix it here... 🙂 )
Great compilation Chandoo
For the "Clean your text before you lookup"
=VLOOKUP(CLEAN(TRIM(E20)),F5:G18,2,0)
I would like to share a method to convert a number-stored-as-text before you lookup:
=VLOOKUP(E20+0,F5:G18,2,0)
@Peder, yeah, I loved that formula
@Aires: Sorry, I misunderstood your formula. Corrected the heading now.
@John.. that is a cool tip.
Hey Chandoo,
That p-value formula is really great for a statistics person like me.
What a p-value essentially is, is the probability that the results obtained from a statistical test aren't valid. So for example, if my p value is .05, there's a 5% probability that my results are wrong.
You can play with this if you install the Data Analysis Toolpak (which will perform some statistical tests for you AND provide the P Value.)
Let's say for example I've got two weeks of data (separated into columns) with the number of hours worked per day. I want to find out if the total number of hours I worked in week two were really all the different than week one.
Week1 Week2
10 11
12 9
9 10
7 8
5 8
Go to Data > Data Analysis > T-Test Assuming Unequal Variances > OK
In the Variable 1 Box, select the range of data for week 1.
In the Variable 2 Box, select the range of data for week 2.
Check "Labels"
In the Alpha box, select a value (in percentage terms) for how tolerant you are of error.
.05 is the general standard; that is to say I am willing to accept a 95% level of confidence that my result is accuarate.
Select a range output.
Excel calculates a number of results: Average (mean) for each week's data, etc.
You'll notice however that there are two P Values; one-tail and two-tail. (one tail tests are for > or .05), the number of hours I worked in week two is statistically equivalent to the number of hours I worked in week one.
So here’s a way you might want to use this. You put up a new entry on your blog. You think it’s the best entry ever! So you pull your webstats for this week and compare it to last week. You gather data for each week on the length of time a visitor spends on your website. The question you’re trying to prove statistically is whether there’s an average increase in the amount of time spent on your website this week as compared to last week (as a result of your fancy new blog post). You can run the same statistical test I illustrated above to find out. Incidentally, it matters very little to the stat test whether the quantity of visitors differs or not.
Anyhow, the Data Analysis toolpack doesn't perform a lot of stat tests that folks like me would like to have access to. In those cases I have to either use different software, or write some very complicated mathematical formulas. Having this p-value formula makes my life a LOT easier!
Thanks!
Eric~
Fantastic stuf..One line explanation is cool.
Thanks to all the contributors
OS
Take FirstName, MI, LastName in access (you can fix it to work in excel) capitalize first letter of each and lowercase the rest and add ". " if MI exists then same for last name:
Full Name: Format(Left([FirstName],1),">") & Format(Right([FirstName]),Len([FirstName])-1),"") & ". ","") & Format(Left([LastName],1),">") & Format(Right([LastName],Len([LastName])-1),"<")
I teach excel, access, etc etc for a living and i have my access students build this formula one step at a time from the inside out to show how formulas can be made even if it looks complicated. Yes I know I could just do IsNull([MI]) and reverse the order in the Iif() function but the point here is to nest as many functions as possible one by one (also I illustrate how it will fail without the Not() as it is)
Extract the month from a date
The easiest formula for this is =MONTH(a1)
It will return a 1 for January, 2 for February etc.
if in a column we write the value of total person for eg. 10 if we spent 1.33 paise each person then how we get total amount in next column and the result will in round form plzzzzz solve my problem sir................... thank u
@Anjali
If the value 10 is in B2 and 1.33 paise is in C2 the formula in D2 could be =B2*C2
If the values are a column of values you can copy the formula down by copy/paste or drag the small black handle at the bottom right corner of cell D2
kindly share with me new forumulas.
How to convert a figure like 870.70 into 870 but 871.70 into 880 using excel formula ? Please help.