The Warren Housing Index
Warren Township, Somerset County, New Jersey. Updated by John Mangini, NextHome Premier.
The Warren Housing Index is the median closed price per square foot of living area for homes sold in Warren Township, Somerset County, New Jersey, indexed so that the year 2000 equals 100. It reads 219.7 for the trailing twelve months ending August 16, 2026, based on the 119 closed sales in that window with a computable price per square foot at a median of $406.78. That is 0.6 percent above the reading a year earlier.
Calendar year readings. The dashed final segment and open marker are the current year to date, which is provisional. Source: Garden State MLS closed sales, Warren Township (Somerset County) only.
What it measures
The index tracks the median closed price per square foot of living area for homes sold in Warren Township, indexed so that the year 2000 equals 100. Square footage comes from county tax records rather than agent entered remarks, which keeps the denominator consistent across two and a half decades of listings.
Why price per square foot and not median price
Median sale price moves when the mix of homes changes. A quarter heavy on estate lots reads as appreciation even when nothing appreciated. Price per square foot is not immune to mix, but it removes the largest single distortion, and it lets a 1,900 square foot ranch and a 5,200 square foot colonial sit in the same series.
Rules of construction
- Warren Township, Somerset County only. Warren County is a different place and is never included.
- Closed sales only. Listings under contract and expired listings are excluded.
- Superseded duplicate records are filtered out before the median is taken.
- Observations outside a band of 50 to 1,500 dollars per square foot are dropped as data errors.
- Living area comes from the merged tax and parcel record, with the MLS approximate square footage used as a fallback.
- The current year is a partial year and will move as more closings record.
The headline reading is a trailing twelve month figure. It covers the last full year of closings regardless of where the calendar sits, which keeps it from swinging on seasonality. The chart and the table are calendar year readings, and the final point is a partial year. Both are built the same way. They differ because they cover different spans of time.
The full series, 2000 to today
| Year | Sales in index | Median $/sf | Index |
|---|---|---|---|
| 2026 (partial) | 52 | $401.35 | 216.8 |
| 2025 | 164 | $408.23 | 220.5 |
| 2024 | 169 | $390.40 | 210.9 |
| 2023 | 184 | $351.53 | 189.9 |
| 2022 | 226 | $311.26 | 168.1 |
| 2021 | 239 | $292.85 | 158.2 |
| 2020 | 130 | $242.56 | 131.0 |
| 2019 | 112 | $243.38 | 131.5 |
| 2018 | 112 | $255.57 | 138.0 |
| 2017 | 107 | $260.42 | 140.7 |
| 2016 | 105 | $248.23 | 134.1 |
| 2015 | 89 | $252.73 | 136.5 |
| 2014 | 103 | $255.20 | 137.8 |
| 2013 | 111 | $250.93 | 135.5 |
| 2012 | 101 | $242.66 | 131.1 |
| 2011 | 73 | $233.21 | 126.0 |
| 2010 | 66 | $236.31 | 127.6 |
| 2009 | 58 | $216.24 | 116.8 |
| 2008 | 74 | $239.96 | 129.6 |
| 2007 | 98 | $279.99 | 151.2 |
| 2006 | 71 | $278.13 | 150.2 |
| 2005 | 88 | $272.42 | 147.1 |
| 2004 | 90 | $254.22 | 137.3 |
| 2003 | 87 | $225.64 | 121.9 |
| 2002 | 107 | $214.58 | 115.9 |
| 2001 | 54 | $207.90 | 112.3 |
| 2000 | 65 | $185.14 | 100.0 |
An index of 200 means a square foot of Warren housing costs twice what it cost in 2000 in nominal dollars. The index is not inflation adjusted and it is not a forecast. It is a record of what has already closed.
Warren Township is in Somerset County
Warren Township, ZIP code 07059, sits in Somerset County, New Jersey. It is frequently confused with Warren County, a separate county in the northwest of the state that contains Belvidere, Phillipsburg and Hackettstown. This index covers Warren Township in Somerset County and nothing else.