Calculating quintiles, an
example:
|
Incomes |
Step 1 |
Step 2 |
Step 4 |
Step 5 |
Average |
|
|
|
|
|
|
|
|
12000 |
2000 |
2000 |
|
|
|
|
6000 |
3000 |
3000 |
5000 |
7% |
2500 |
|
4000 |
4000 |
4000 |
|
|
|
|
15000 |
4000 |
4000 |
8000 |
12% |
4000 |
|
8000 |
5000 |
5000 |
|
|
|
|
4000 |
6000 |
6000 |
11000 |
16% |
5500 |
|
2000 |
8000 |
8000 |
|
|
|
|
9000 |
9000 |
9000 |
17000 |
25% |
8500 |
|
5000 |
12000 |
12000 |
|
|
|
|
3000 |
15000 |
15000 |
27000 |
40% |
13500 |
|
|
|
|
|
|
|
|
|
Step 3 |
68000 |
|
100% |
|
|
|
|
|
|
|
|
Steps
1
Put
the values in numerical order from lowest to highest.
2
Divide
the sorted values into fifths. In the
above example there are ten values, so there are 2 values in each fifth. If
there were 40 values, then there would be 8 numbers in each fifth.
3
Calculate
the total value for all cases. In the
above example we would add up all the incomes.
4
Calculate
the total amount in each quintile. In
the above example, add up all the incomes in each quintile.
5
Calculate
the percentage of the total amount for each quintile. In the above example, calculate what percent of the total income
is earned by each quintile. The lowest
quintile would earn:
5000/68000 x 100%
When
you have completed step 5, you have calculated the inequality in income. If there was perfect equality, each quintile
would have 20% of the total income.
You
can also calculate the ratio of the amount earned by the highest quintile to
the amount earned by the lowest quintile.
The higher this ratio, the greater the inequality. Perfect equality would give a ratio of 1
(the amount earned by each group would be the same). In the above example, the ratio would be:
27000 / 5000, or
5.4
You
can also calculate the average income earned by each quintile. For each quintile count the total income,
and divide by the number of cases in each quintile. In the above example the individuals in the poorest quintile earn
an average of 2,500 while those in the highest quintile earn an average of
13500.
|
1,400 |
|
700 |
|
4,500 |
|
800 |
|
3,750 |
|
1,500 |
|
700 |
|
1,050 |
|
325 |
|
700 |
|
1,550 |
|
700 |
|
1,600 |
|
750 |
|
2,000 |
|
500 |
|
1,250 |
|
2,500 |
|
750 |
|
2,750 |
|
750 |
|
800 |
|
2,750 |
|
900 |
|
4,500 |
|
800 |
|
1,300 |
|
500 |
|
550 |
|
1,350 |
|
950 |
|
300 |
|
1,050 |
|
350 |
|
1,450 |
|
700 |
|
450 |
|
1,050 |
|
450 |
|
1,050 |
|
800 |
|
4,000 |
|
1,050 |
|
300 |
|
3,250 |
|
800 |
|
1,050 |
|
450 |
|
800 |
|
2,750 |