Formulae [2]
1. For Individual or Discrete Data:
\[\mathrm{D}_j=j\left(\frac{n+1}{10}\right)^\text{th Observation}\mathrm{~where~}j=1,2...9\]
2. For Grouped (Continuous) Data:
\[\mathbf{D}_j=l+\left(\frac{\frac{jn}{10}-cf}{f}\right)\times h,\quad j=1,2...9\]
Where
D = Decile
l = Lower limit of decile class
f = Frequency of decile class
cf = Cumulative frequency of class preceding decile class
h = Upper limit of the class – lower limit of the decile class.
A. For Individual or Discrete Data
Formula:
\[\mathrm{P}_k=\mathrm{size~of}k\left(\frac{n+1}{100}\right)^\text{th Observation}\] k = 1, 2,... 99
Where:
- k = Percentile number (1 to 99)
- n = Total number of observations
B. For Grouped/Continuous Data
Formula:
\[\mathbf{P}_k=l+\left(\frac{\frac{kn}{100}-cf}{f}\right)\times h\] k = 1, 2,... 99
Where
P = Percentile
l = Lower limit of percentile class
f = Frequency of percentile class
cf = Cumulative frequency of class preceding percentile class
h = Upper limit of the class – lower limit of the percentile class.
