ZIP 37138 vs ZIP 37115

This side-by-side compares ZIP 37138 (Old Hickory, TN) and ZIP 37115 (Madison, TN) using the same Census ACS 5-Year table fields for both — no averages swapped in, no national proxies. ZIP 37138 has a population of 22,191 at 483 people per square mile, while ZIP 37115 has 37,316 at 677 per square mile. That difference in population size and density alone reshapes how every other metric should be interpreted — a higher-income ZIP with 1,200 residents behaves very differently from one with 45,000.

On income and education, ZIP 37138 reports a median household income of $85,149 against $54,566 in ZIP 37115, with per-capita income of $47,633 vs $33,272. The share of adults holding a bachelor's degree or higher is 34.3% in 37138 and 25.6% in 37115. Poverty rate reads 8.2% vs 17.0%, and unemployment 2.6% vs 5.1% — these four fields alone drive most of the difference in the scorecard grades you will see for each ZIP.

Housing separates these two ZIPs further: median home value sits at $363,000 in 37138 versus $307,500 in 37115, with median rent of $1,526 and $1,320 per month respectively. Homeownership rate is 77.2% vs 43.3%. When reading the comparison table below, focus on paired metrics rather than single winners — a ZIP with lower home values and lower income is not strictly "worse" if rent-to-income ratios and commute times land in the same zone. Every value is pulled from the exact same ACS table so the two columns are genuinely comparable.