draw lorenz curve
INCOME-- 2500 7500 15000 30000 45000
NO. OF PEOPLE-- 5 10 28 10 7
Steps in making the lorenz curve:
i. Calculate the cumulative income of the class.
ii. Calculate the cumulative percentage or percentage of income of the class by using the given formula,
iii. Calculate the cumulative frequency.
iv. Calculate the cumulative percentage if frequency or the percentage of people earning income Y, by using the given formula
Income (Y) | Cumulative Income | Cumulative percentage | No. of people (Frequency) | Cumulative Frequency | Cumulative percentage of frequency |
2500 | 2500 | 2.5 | 5 | 5 | 8.3 |
7000 | 9500 | 9.5 | 10 | 15 | 25 |
15000 | 24500 | 24.6 | 28 | 43 | 71.6 |
30000 | 54500 | 54.7 | 10 | 53 | 88.3 |
45000 | 99500 | 100 | 7 | 60 | 100 |
v. Plot cumulative percentage (percentage of income) on the y-axis and cumulative frequency (percentage of people) on the x-axis.
vi. Join the pints, you will get a lorenz curve, similar to the lorenz curve given below.