Business Statistics

Chapter 3 | Measures of Central Tendency 101

3.7.7 Percentiles

In a data series, when observations are arranged in an ordered sequence, percentiles divide the data

into 100 equal parts. For an individual series and a discrete frequency distribution, the generalized

formula for computing percentiles is given as

( 1)

100

k

k N

P

+

=

where k = 1, 2, 3, …, 99 and N = f. Hence,

1 99

1 ( 1) 99 ( 1)

and

100 100

N N

P P

⋅ + ⋅

+

= =

In the case of a continuous frequency distribution, the generalized formula for computing percentiles

is given as

( /100)

k

kN c

P i

f

−

= + ×

where k = 1, 2, 3, …, 99. Other symbolic notations are as explained earlier.

MS Excel can be used ...