| Index | Duncan | Iowa | National |
| Income per capita | $35,669 | $42,672 | $44,883 |
| Median household income | $93,977 | $81,387 | $81,333 |
| Median income owner occupied | $94,245 | $98,724 | $106,172 |
| Median income renter occupied | $0 | $45,890 | $52,080 |
| Median earnings male | $0 | $54,047 | $54,343 |
| Median earnings female | $0 | $36,462 | $38,439 |
| Unemployment rate | 0.0% | 3.2% | 4.9% |
| Poverty level | 41.2% | 12.3% | 15.1% |

| Labour Type | Male | Female |
| Construction industry | 0.0% | 0.0% |
| Manufacturing sector | 0.0% | 0.0% |
| Financial & insurance services | 0.0% | 0.0% |
| Wholesale & retail services | 34.4% | 34.4% |
| Public administration | 0.0% | 0.0% |
| Transportation, warehousing & utilities | 0.0% | 0.0% |
| Education, health & social services | 0.0% | 0.0% |
| Other | 65.6% | 65.6% |
| City | Population | Household Income | National Avg. |
| Ventura, IA | 783 | $109,441 | 34.6% |
| Meservey, IA | 286 | $108,545 | 33.5% |
| Crystal Lake, IA | 269 | $95,718 | 17.7% |
| Garner, IA | 3,134 | $93,156 | 14.5% |
| Kanawha, IA | 983 | $93,004 | 14.3% |
| Duncan, IA | 104 | $93,977 | 15.5% |
| City | Population | Household Income | National Avg. |
| Whale Pass, AK | 104 | $64,235 | 21.0% |
| Phillipsville, CA | 104 | $3,790 | 95.3% |
| Rutherford, CA | 104 | $148,763 | 82.9% |
| Maysville, CO | 104 | $0 | 100.0% |
| Center Junction, IA | 104 | $0 | 100.0% |
| Duncan, IA | 104 | $93,977 | 15.5% |