PlanMaker QUARTILE: Five-Number Summaries and Worked Examples
Use PlanMaker QUARTILE selectors, reproduce the official example and compare inner spread with an extreme observation using complete numeric worksheets.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
QUARTILE selects a minimum, lower quartile, median, upper quartile or maximum from numeric data. Its second argument is a selector from 0 through 4. Use 3 for the upper quartile; 0.75 is a percentile fraction, not the selector used by the documented example.
Availability and version history
- Introduced: Documented by the PlanMaker 2010 manual; the original introduction release and date are not established.
- Availability: Documented in PlanMaker 2026. This checked version is not a final supported-version endpoint.
- Scope: Current reference belongs to the PlanMaker 2026/NX manual family. FreeOffice and individual mobile-build availability are not established here.
- Checked: October 14, 2026, against the official QUARTILE reference and historical manual. Additional calculations are explicitly scoped models; no native PlanMaker test was performed.
Syntax and the five selectors
=QUARTILE(Range, n)
Both arguments are required. The official entry describes a numeric range and these selector meanings:
| n | Requested value |
|---|---|
| 0 | Minimum |
| 1 | First quartile, or 25th percentile |
| 2 | Median, or 50th percentile |
| 3 | Third quartile, or 75th percentile |
| 4 | Maximum |
It specifies #NUM! when n is below 0 or above 4. The examples here use integer selectors; the page does not explain how a fractional selector is converted.
QUARTILE remains documented. The newer QUARTILE.INC reference states that it returns the same result. A newer identical name is not a retirement notice, and a change to the exclusive function can change the statistical convention.
Reproduce the published example
Create VendorQuartile with 1 through 9 in A1:A9, without a header in that range. Enter =QUARTILE(A1:A9,3) in C1. The documented result is 7, the same as =PERCENTILE(A1:A9,0.75) in C2.
In C3 enter =QUARTILE.INC(A1:A9,3) for the same documented result. The separate QUARTILE.EXC example returns 7.5 for selector 3. Keep those conventions distinct even when the median agrees.
The 2010 manual already gives the same QUARTILE syntax, selector meanings and example. Its range description includes arrays; the current short entry emphasizes numeric cell ranges. The examples here use explicit numeric ranges and do not establish every historical array-entry method.
A complete five-number worksheet
Create DeliveryQuartiles, using A1:H10. Enter Hours in A1 and 5,8,9,12,14,18,20,30 in A2:A9. These eight observations are already sorted. Put Selector, QUARTILE, Inclusive comparison and Difference in C1:F1, then enter 0,1,2,3,4 in C2:C6.
- D2:
=QUARTILE($A$2:$A$9,C2) - E2:
=QUARTILE.INC($A$2:$A$9,C2) - F2:
=D2-E2
Fill D2:F2 through row 6.
| Selector | Expected D and E under the stated model |
|---|---|
| 0 | 5 |
| 1 | 8.75 |
| 2 | 13 |
| 3 | 18.5 |
| 4 | 30 |
For the interior quartiles, these checks use the inclusive interpolation position h=1+(Nā1)k, where N is the number of observations and k=n/4. At h=j+d, interpolate from sorted value j toward value j+1 by fraction d. Q1 has h=2.75 and is 8+0.75Ć(9ā8)=8.75; Q3 has h=6.25 and is 18+0.25Ć(20ā18)=18.5. The median is (12+14)/2=13.
This model matches the vendor’s published example, but the short PlanMaker entry does not state its complete interpolation algorithm. The broader outputs are independently calculated expectations, not native-tested implementation claims. NIST’s percentile discussion describes these alternative interpolation conventions.
F has a zero target from the vendor’s stated equality of QUARTILE and QUARTILE.INC. Put =MEDIAN(A2:A9) in H2 for 13, =D5-D3 in H3 for the model interquartile range 9.75 hours, and =D6-D2 in H4 for the full range 25 hours.
Advanced: change an extreme observation
Copy DeliveryQuartiles to LongDelay. Change only A9 from 30 to 50. The data remain sorted; the minimum, Q1, median and Q3 model values stay 5,8.75,13,18.5, while the maximum becomes 50.
H3 remains 9.75, but H4 becomes 45. The interquartile range describes the middle part of this particular dataset and does not respond to this change in the last observation. That does not mean the extra delay is unimportant or should be discarded. Keep the original records and inspect both the full range and inner spread.
This is a controlled one-value change. Other changes can alter the ordering and quartiles; a static sorted copy must be rebuilt when its source changes.
Interpretation and limits
A quartile is a threshold value, possibly interpolated between observations. It does not assign every record to one of four equally sized groups, especially when data tie. The interquartile range has the same units as the inputs; it is not a variance or a squared quantity.
Blank-only ranges, mixed text and logical values, exact native precision and fractional selectors remain outside these examples. Keep dates and units separate from the numeric measurements unless the model explicitly defines their treatment.
Related guides: QUARTILE.INC, QUARTILE.EXC, PERCENTILE and MEDIAN.