| year | total income | wage income | operating income | property income | transfer income |
| 2004-2006 | 11.01% | 14.47% | 7.87% | 15.17% | 23.20% |
| 2007-2010 | 13.38% | 15.34% | 10.12% | 19.23% | 26.32% |
| 2011-2013 | 14.57% | 18.33% | 10.25% | 13.22% | 20.17% |
| 2015-2018 | 8.65% | 9.62% | 6.04% | 11.42% | 11.69% |