Types of Index Numbers
    Index  numbers  are  classified  on  the  basis  of  the 
    phenomena whose changes they measure. In the economic 
    and  business,  index  numbers  can  be  classified  into  the 
    following types:
            Price Index             Quantity Index             Value Index 
            Price Index             Quantity Index             Value Index 
             Numbers                   Numbers                  Numbers
             Numbers                   Numbers                  Numbers
            Simple and 
            Simple and              Cost of Living          Special Purpose 
            Aggregative             Cost of Living          Special Purpose 
            Aggregative            Index Numbers             Index Numbers
          Index Numbers            Index Numbers             Index Numbers
          Index Numbers
         Methods of Construction of Index Numbers
                                                             Simple 
                                                          Aggregative 
                               Simple Index                 Method
                                Numbers                Simple Average of 
                                                       Quantity Relatives 
    Methods of                                              Method
    Constructing 
   Index Numbers                                           Weighted 
                                                          Aggregative 
                                                            Method
                             Weighted Index 
                                Numbers
                                                       Weighted Average 
                                                          of Quantity 
                                                       Relatives Method
                      Simple Aggregative Method
       ∑ P                                             ∑ Q
           1                                              1
                                             Q   = ---------  X   100
  P01  = ---------  X   100                    01
                                                 ∑ Q
       ∑ P                                            0 
           0 
                                            Where, 
 Where,                                     ∑ Q1  = Aggregate of quantity in 
 ∑ P  Aggregate of Prices in Current Year   Current Year
     1  =                                   ∑ Q   Aggregate of quantity in Base 
                                                0 = 
 ∑ P0 = Aggregate of Prices in Base Year    Year
   P   Prices Index                         Q01   =   Quantity Index
    01  = 
                     Simple Aggregative Method
           Commodity              Quantity in 2010           Quantity in 2018 
                  A                         50                        60
                  B                         40                        40
                  C                         30                        35
                 D                          10                        15
                  E                         5                         15
                                       ∑ Q  = 135                 ∑ Q  = 165
                                           0                          1
          ∑ Q
                1
      Q   = ---------  X   100
        01
          ∑ Q
                0
             = 165/ 135 x 100
             = 122.22
                 
      Simple Average of Quantity Relatives Method
      When Arithmetic Mean is Used 
        ∑ Q
    Q   = ---------  
     01
          N
      Q
       1
   Q = ---------  X   100
       Q
        0