Divide Time Period across different Time Frames (Calculating Interest) - excel

In the attached excel file
http://www.sendspace.com/file/y9qj0t
I've got a time period "C3:D3" (time periods can be altered by user) and a sum of money for which i need to calculate interest across different time periods with different interest rates.
You can check out my formula in "E6:E" but somehow I'm not postive it's correct.
I want the formula to divide days of the above period of time across the different int. rates time frames & return "0" when int.rates times frames are before or after my time period.
Also, I'm not certain how to handle the last int. rate time frame (ie the last time int. rate was changed so it's not a closed time frame B50:C50). B50 is occupied by the last date int. rate was changed and C50 equals above mentioned D3. Does it make any sense?
Thanks for any help!

I was going to answer your previous question....but you deleted it...
Your method works, I think, but this formula can give you the correct result in a single cell without using columns E and F
=SUMPRODUCT(LOOKUP(ROW(INDIRECT(C3&":"&D3-1)),B6:D50))/365*E3
it doesn't matter what value you put in C50
The ROW/INDIRECT part gives you an "array" of all dates from C3 to D3-1 and that array is the lookup value for LOOKUP function, looking up each date in B6:B50 and returning the corresponding rate from D6:D50. SUMPRODUCT then sums all those rates. Diving by 365 then gives you the average annual rate. I get 2.89 for your example, the same as your result

Related

How can I (easily) format long intervals (over 30 days, but including time components)

I am using a spreadsheet to record the intervals between certain medical events. Each event's timestamp is recorded in one column, so the interval between each event is the difference between consecutive cells (and the time since the last event uses now()).
First problem: I want to display the interval in days, hours and minutes. None of the built-in formats will do this, they report the days remaining after discarding complete months. So I am using this expression:
TEXT(TRUNC(C2-C1),"0") & " days " & TEXT(MOD(C2-C1,1),"hh "" hrs "" mm ""mins""")
which (e.g.) shows "46 days 13 hrs 44 mins". I was hoping there was a way to format a date/time value to show this rather than making the cell a string value, but I haven't been able to find one.
Second problem: I want to display the average value of all completed intervals in the same format. Because I can't average the string values produced by the previous expression I need to average the numeric equivalent (which I'd prefer not to have visible in the sheet) and then convert it to a string as for a single interval.
I can probably do this with a similar approach (if I don't run out of characters to enter the formula) but it seems to me that there must be a better way.
Ideally there is a solution which will work in Excel 2010. Has anyone solved a similar problem before and can give me some pointers?
Thanks, T
Edit: Some data to show what I am working with (I hope the image is readable). Here's a few lines from the sheet.
The formula for H2 etc. is
=IF(G2="c",NOW()-C2,"")
I5 is calculated as the difference between C5 and Cprev (where prev is chosen so that D5 and Dprev are both set). Obvious extension of this for J and K.
M2, M3 and M4 are respectively
=AVERAGEIF(K5:(INDIRECT("K"&(ROWS(K:K)))),"<>0")
=AVERAGEIF(J5:(INDIRECT("J"&(ROWS(J:J)))),"<>0")
=AVERAGEIF(I5:(INDIRECT("I"&(ROWS(I:I)))),"<>0")
Now, I can use a custom format for the values in H, I and J, and for M3 and M4, because these values will never exceed a few days. But values in K and M2 will be somewhere around 100 so I can't just format the raw value.
With custom formatting applied:
Here K6 and M2 say "27 days.." not "87 days..". That's what I'd like to fix nicely, hopefully without populating additional cells or writing a 3gl function to do it.
Date_Times in Excel are stored as days (with the decimal part representing parts of a day).
If the date matters, rather than just a number of days, then day zero is 1899/12/31.
Your first thought was right - do with formatting, not by turning a number into a string.
Entering date into A and time into B, with C=A+B is a good start, so that you can E.g. subtract one point in time from another without having to do anything about straddling midnight, month-ends etc, calculate averages etc.
Consolidating the comments already here: per https://support.microsoft.com/en-us/office/format-numbers-as-dates-or-times-418bd3fe-0577-47c8-8caa-b4d30c528309 you cannot get d for days above 31 (and it won't accept a format 0 hh:mm:ss )
I suggest that you do all your calculations using just numbers to get to say column M, and in N2 put =M2 etc, so you have the same values twice.
Then for formatting, use Format Cells | Number | Custom.
In column M put 0 "days".
In column N put hh "hours" mm "minutes".

Excel average if function for obtaining hourly data

I have minute data for air temperature and relative humidity (about 930,000 cells) for a building and I am trying to obtain the hourly average using excels "AverageIF" function. Here's the criteria that I have come up with: whenever one hour passes, average the air temperature and relative humidity for that hour. I am having trouble communicating these criteria to excel and any help would be appreciated. I have included a pic of what my data looks like:
the yellow row is me manually adding a row after an hour has passed and calculated the average using the average function.
In the example above I went a bit long winded in the formula to deal with time intervals where there was no data, as that generates a divide by 0 error.
Essentially what I did was setup a summary table to the right. I gave a start and end time for each hour (ASSUMING this is based on a 24 hour clock and not 1 hour from some arbitrary start time)
I used the AVERAGEIFS function as you have two criteria. Everything after a start time and everything before an end time. Only lines that match BOTH criteria are included.
The basic formula looks like this and is based on my example cell J4:
AVERAGEIFS(E$4:E$31,$C$4:$C$31,">="&$H4,$C$4:$C$31,"<="&$I4)
If the date is important, then you would need to add a date column to the table on the right and add a third criteria to the formula above.
In order to deal with divide by zero error and display blank instead of zero so you can distinguish between actual average of 0 and no data and still presenting an error when another type of error comes up I use the following formula in J4:
=IFERROR(AVERAGEIFS(E$4:E$31,$C$4:$C$31,">="&$H4,$C$4:$C$31,"<="&$I4),IF(ERROR.TYPE(AVERAGEIFS($E$4:$E$31,$C$4:$C$31,">="&$H4,$C$4:$C$31,"<="&$I4))=2,"","ERROR"))
The above formulas can be copied down and to the right.

Finding a shorter period of days within a longer period for calculation

I have a set of dates, in total 7 periods spanning 6 months each with corresponding calculation factor.
I will have user input of period for which they'd want the calculation to be done, which can fall within one of the 6 months periods or encompass between two or more such periods wholly or partially.
Illustration:
The preset periods:
User input:
I've obtained decimal value (monthly basis) of the periods input by the user for calculation. For first instance (see user input), the decimal value for the period 01-01-2015 to 29-04-2015 will be 3.97 on monthly basis. The calculation for that period would be like:
n*3.97*113%
For the second instance, the decimal value for the period 30-04-2015 to 30-06-2015 would be 2.03, which would be used to do calculation at 113% and then the result will be added to the calculation done at 119% using the decimal value 5.65 for the period 01-07-2015 to 20-12-2015:
(n*2.03*113%)+(n*5.65*119)
Think I can handle the breaking up of periods since the revision event is bi-annual on particular dates but advice regards to that is welcome. More importantly, I need help tracing the preset calculation factor (say 132%) corresponding to the period input by the user as illustrated above. Is it feasible?
I will use the standard approach for finding the overlap between two dates and will split the task into three parts as in my answer to this recent question.
(1) The first part is finding the overlap between the user's range of dates and one or more revision periods in whole months and will need an array formula. I have chosen to use the Datedif function 1 to get the difference in months between the beginning and end of the overlaps. If there is no overlap, the start date fed in to Datedif will be after the end date, and it will return an error which can be trapped by Iferror. If the user's dates start in A2 and B2, this gives in C2:
=SUM(IFERROR((DATEDIF(IF(K$2:K$8>A2,K$2:K$8,A2),IF(L$2:L$8<B2,L$2:L$8,B2),"m")+1)*M$2:M$8,0))
which has to be entered as an array formula using CtrlShiftEnter
The above result includes the first and last months entered by the user even if they are incomplete months. It's then necessary to subtract any missing days in the first and last months.
(2) Missing days in first month as a fraction of the number of days in that month in D2:
=SUMIFS($M$2:$M$8,$K$2:$K$8,"<="&A2,$L$2:$L$8,">="&A2)*(A2-EOMONTH(A2,-1)-1)/(EOMONTH(A2,0)-EOMONTH(A2,-1))
A noted by OP, this could also have been done using sumproduct, vlookup or index/match.
(3) Missing days in last month as a fraction of days in that month in E2:
=SUMIFS($M$2:$M$8,$K$2:$K$8,"<="&B2,$L$2:$L$8,">="&B2)*(EOMONTH(B2,0)-B2)/(EOMONTH(B2,0)-EOMONTH(B2,-1))
The total is just (1)-(2)-(3) or
=C2-D2-E2
I have put the results of OP's two examples for comparison in H2 and H3: my results agree with them in the first 3 significant figures.
n*3.97*113%
(n*2.03*113%)+(n*5.65*119)
In all cases I have set n=1 and ignored the fact that the rate is a percentage.
This shows how the results would be calculated manually:
1 Pros of using Datedif:
(1) Works across year boundaries unlike just using Month function.
(2) Works conveniently with Iferror to identify non-matching date ranges.
Cons of using Datedif:
(1) It is an undocumented function and may be withdrawn in future.
(2) In this particular case, all date calculations are within the same year so Month would be useable.

Excel AVERAGEIFS else statement

I'm trying to perform an AVERAGEIFS formula on some data, but there are 2 possible results and as far as I can tell AVERAGEIFS doesn't deal with that situation.
I basically want to have an ELSE inside it.
At the moment I have 2 ranges of data:
The first column only contains values 'M-T' and 'F' (Mon-Thurs and Fri).
The second column contains a time.
The times on the rows with an 'F' value in column 1 are an hour behind the rest.
I want to take an average of all the times, adjusting for the hour delay on Fridays.
So for example I want it to take an average of all the times, but subtract 1 hour from the values which are in a row with an 'F' value in it.
The way I've been doing it so far is by having 2 separate results for each day, then averaging them again for a final one:
=AVERAGEIFS(G3:G172, B3:B172, "M-T")
=AVERAGEIFS(G3:G172, B3:B172, "F")
I want to combine this into just one result.
The closest I can get is the following:
=AVERAGE(IF(B3:B172="M-T",G3:G172,((G3:G172)-1/24)))
But this doesn't produce the correct result.
Any advice?
Try this
=(SUMPRODUCT(G3:G172)-(COUNTIF(B3:B172,"=F")/24))/COUNTIF(B3:B172,"<>""""")
EDIT
Explaining various steps in the formula as per sample data in the snapshot.
SUMPRODUCT(G3:G17) sums up all the value from G3 to G17. It gives a
value of 4.635416667. This after formatting to [h]:mm gives a value
of 111.15
OP desires that Friday time be one hour less. So I have kept one hour less for Friday's in the sample data. Similar SUMPRODUCT on H3:H17 leads to a value of 4.510416667. This after formatting to [h]:mm gives a value
of 108.15. Which is exactly three hours less for three occurrences of Fridays in the sample data.
=COUNTIF(B3:B17,"=F") counts the occurrences of Friday's in the B3:B17 range which are 3 occurrences.Hence 3 hours have to less. These hours are to be represented in terms of 24 hours hence the Function COUNTIF() value is divided by 24. This gives 0.125. Same is the difference of 4.635416667 and 4.510416667 i.e. 0.125
Demonstration column H is for illustrative purposes only. Infact Friday accounted values that is 108.15 in sample data has to be divided by total data points to get the AVERAGE. The occurrences of data points are calculated by =COUNTIF(B3:B17,"<>""""") with a check for empty columns.
Thus 108:15 divided by 15 data points give 7:13 in the answer.
Revised EDIT Based upon suggestions by #Tom Sharpe
#TomSharpe has been kind enough to point the shortcomings in the method proposed by me. COUNTIF(B3:B172,"<>""""") gives too many values and is not advised. Instead of it COUNTA(B3:B172) or COUNT(G3:G172) are preferable. Better Formula to get AVERAGE as per his suggestion gives very accurate results and is revised to:
=AVERAGE(IF(B3:B172="M-T",G3:G172,((G3:G172)-1/24)))
This is an Array Formula. It has to be entered with CSE and further cell to be formatted as time.
If your column of M-T and F is named Day and your column of times is named TIME then:
=SUMPRODUCT(((Day="M-T")*TIME + (Day="F")*(TIME-1/24)))/COUNT(TIME)
One simple solution would be to create a separate column that maps the time column and performs the adjustment there. Then average this new column.
Is that an option?
Ended up just combining the two averageifs. No idea why I didn't just do that from the start:
=((AVERAGEIFS(G$3:G171, $B$3:$B171, "F")-1/24)+AVERAGEIFS(G$3:G171, $B$3:$B171, "M-T"))/2

Dividing time to get a percentage

Here's my setup: I'm making a log for a time event I'm doing (think of it like sprinting), with a cumulative time broken up into segmented times, formatted as [hh:mm:ss.000] time values.
What I want to do is figure out how much time of a segment is of the cumulative time in the form of a percentage.
What I'm looking to do is basically do A6(segment)/A10(cumulative time)*100, however that formula obviously doesn't work.
If stop watch times (start at 0 in A1) then try in B2 copied down to suit and formatted as Percentage:
=(A2-A1)/A$10

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