The following table shows the income (in ₹) of five different persons (A, B, C, D, E) over given 4 years.
| Years | 2015 | 2016 | 2017 | 2018 |
| A | 12000 | 12500 | 13000 | 13500 |
| B | 10000 | 11000 | 12000 | 13000 |
| C | 5000 | 6000 | 7000 | 8000 |
| D | 20000 | 25000 | 30000 | 35000 |
| E | 15000 | 16000 | 17000 | 18000 |
Find the average income of the five persons in year 2015.