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Central Tendency Dispersion CV Position & Ranking Skewness Kurtosis ToolPak Report
On this page
  1. 1. Measures of Central Tendency
  2. 2. Measures of Dispersion
  3. 3. Position and Ranking
  4. 4. Shape of Distribution — Skewness and Kurtosis
  5. 5. Descriptive Statistics Report via Data Analysis ToolPak
  6. Comparison: Functions vs ToolPak
  7. Key Take-aways

1. Measures of Central Tendency

StatisticExcel FunctionComment
Arithmetic Mean=AVERAGE(range)Sum / Count
Median=MEDIAN(range)Middle value
Mode (single)=MODE.SNGL(range)Most frequent value
Mode (multiple)=MODE.MULT(range)Array formula — returns all modes
Geometric Mean=GEOMEAN(range)For positive values only; growth rates
Harmonic Mean=HARMEAN(range)Reciprocal of mean of reciprocals; for speeds/rates
Trimmed Mean=TRIMMEAN(range, percent)Drops extremes; e.g. percent = 0.1 drops 10 % top + bottom
Weighted Mean=SUMPRODUCT(values, weights)/SUM(weights)No single built-in; use SUMPRODUCT
EXAMPLE 1

Marks in A2:A11 = 45, 52, 38, 71, 64, 49, 58, 33, 67, 72.

=AVERAGE(A2:A11) → 54.9; =MEDIAN(A2:A11) → 55.0; =MODE.SNGL(A2:A11) → #N/A (no repeats).

EXAMPLE 2 (GM & HM)

Annual growth rates in B2:B4 = 1.10, 1.20, 1.30 (i.e. 10 %, 20 %, 30 %). =GEOMEAN(B2:B4) = 1.197 → average growth ≈ 19.7 %.

Average speed for equal distances at 40 and 60 km/h in C2:C3: =HARMEAN(C2:C3) = 48 km/h.

2. Measures of Dispersion

StatisticExcel FunctionComment
Range=MAX(range) - MIN(range)—
Variance (sample, ÷ n−1)=VAR.S(range) or =VAR(range)Use for samples
Variance (population, ÷ n)=VAR.P(range) or =VARP(range)Use for the whole population
SD (sample)=STDEV.S(range) or =STDEV(range)√VAR.S
SD (population)=STDEV.P(range) or =STDEVP(range)√VAR.P
Quartile / IQR=QUARTILE.INC(range, q)q = 1 or 3; IQR = Q3 − Q1
Average Absolute Deviation=AVEDEV(range)Mean absolute deviation from mean
Coefficient of Variation (CV)=STDEV.S(range)/AVERAGE(range)*100Unit-free relative dispersion
EXAMPLE 1

For the data of Example 1 above: =VAR.S(A2:A11) ≈ 188.54; =STDEV.S(A2:A11) ≈ 13.73; CV ≈ 13.73/54.9 × 100 = 25.0 %.

EXAMPLE 2 (IQR)

=QUARTILE.INC(A2:A11, 1) → Q1 = 46.0; =QUARTILE.INC(A2:A11, 3) → Q3 = 66.25. IQR = 20.25.

3. Position and Ranking

FunctionPurpose
=RANK.EQ(number, ref, [order])Standard ranking (ties get equal rank, next rank skipped)
=RANK.AVG(number, ref, [order])Ties get the average rank — used for Spearman correlation
=PERCENTRANK.INC(array, x)Percentile rank of x (inclusive, 0–1)
=PERCENTRANK.EXC(array, x)Percentile rank (exclusive)
=PERCENTILE.INC(array, k)kth percentile (k between 0 and 1)
=LARGE(array, k) / =SMALL(array, k)kth largest / smallest value

Note: The third argument of RANK is order: 0 (or omitted) = descending (largest = rank 1); 1 = ascending.

EXAMPLE 1

For marks 45, 52, 38, 71, 64 (A2:A6):

=RANK.EQ(A2, $A$2:$A$6) in B2 returns rank of each cell. Result: 4, 3, 5, 1, 2.

EXAMPLE 2

=PERCENTRANK.INC(A2:A11, 60) tells what percentile a score of 60 corresponds to within the data. =PERCENTILE.INC(A2:A11, 0.9) returns the 90th percentile.

4. Shape of Distribution — Skewness and Kurtosis

FunctionReturns
=SKEW(range)Sample skewness (Fisher–Pearson)
=SKEW.P(range)Population skewness
=KURT(range)Excess kurtosis (so 0 = normal); ≈ \(\gamma_2\)

Interpretation

EXAMPLE 1

Data: 5, 6, 7, 7, 8, 8, 8, 9, 9, 10. =SKEW ≈ −0.36 (slightly left-skewed); =KURT ≈ −0.15 (mildly platykurtic).

EXAMPLE 2

Right-skewed data (income): 20, 22, 25, 28, 30, 35, 50, 80, 120. =SKEW ≈ 1.71 (strong positive skew); =KURT ≈ 2.39 (leptokurtic).

5. Descriptive Statistics Report via Data Analysis ToolPak

Procedure

  1. Enable the ToolPak (Unit 1, Section 7.1).
  2. Data tab → Data Analysis → select "Descriptive Statistics" → OK.
  3. Input Range: select your data column(s).
  4. Tick Labels in first row if your range includes a header.
  5. Choose Output Range (new cell location) or "New Worksheet Ply".
  6. Tick Summary statistics.
  7. Optionally tick Confidence Level for Mean (default 95 %) — gives margin of error.
  8. Click OK.

What the Report Contains

Confidence Interval: CI for mean = Mean ± Confidence Level value. For example, Mean = 75 and Conf. = 4.2 ⇒ 95 % CI ≈ (70.8, 79.2).

Worked Example

EXAMPLE

30 students' marks in A2:A31. Running Descriptive Statistics with Confidence Level 95 % might give:

StatisticValue
Mean58.30
Standard Error2.45
Median56.50
Mode55.00
SD13.42
Sample Variance180.10
Kurtosis−0.34
Skewness0.21
Range56
Min32
Max88
Sum1 749
Count30
Conf. Level (95 %)5.02

So 95 % CI for mean ≈ (58.30 − 5.02, 58.30 + 5.02) = (53.28, 63.32).

Comparison: Functions vs ToolPak

FunctionsToolPak (Descriptive)
Update on data changeYes (live formulas)No — must rerun
Best forCustom or single statOne-shot full report
Output typeSingle cell eachMulti-row table

Key Take-aways