A Gazetteer for the United States and Canada
Census Data for Roca ...
The most recent Census Estimate<1> was for 2017 and it gave Roca a population of 290 people.
The last Decennial Census<2> was in 2010, which gave Roca a population of 220 people.
The village of Roca is located in Lancaster County. The 2010 Census gave Lancaster County a population of 285,407 people. This means that Roca had 0.08% of the county's total population, making it Lancaster's 8th most populous community.
When the Census Bureau conducts a census for a village like Roca, they draw a boundary around the area in which they are going to conduct their count - this defines the sampling area (usually shaped as a polygon). The shape of the sampling area can be quite complex and it's important to keep in mind that the boundaries of the sampling area may or may not match the recognized boundaries of the village.
Things like the population, area and housing for Roca reflect the sampling area. Since the shape of the sampling area and the actual boundaries of Roca might be different, it's best to check with the U.S. Census Bureau to resolve any difference between the two.
The 2010 Census shows that the sampling area for Roca has a total area of 0.14 square miles [0.4 km²].
Lancaster County has a land area of 837 square miles [2,169.2 km²]. At 0.14 square miles [0.4 km²], Roca has 0.02% of the county's total land area.
Not only does the sampling area define boundaries, it also has a GPS location (latitude & longitude) that indicates a point within the sampling area (usually the center of the polygon, known as the centroid). At the time of the 2010 Census, the sampling area was located at:
Lat: 40° 39' 30" (or 40.66°) [Map]
More information on this topic and the changes between the 2000 Census and the 2010 Census can be found in the section for our Census-to-Census Observations ... (see below).
Population Density ...
Using the population (220 people) and land area (0.14 square miles [0.4 km²]) values from the 2010 Census, Roca had a population density of 1,582 people per square mile [611 people/km²].
In comparison, the 2000 Census shows Roca had a population of 220 people and a land area of 0.14 square miles [0.4 km²]. This gives a population density of 1,580 people per square mile [610 people/km²]
NOTE: Be aware that when comparing population density between the 2000 Census and the 2010 Census, there were changes in the sampling area for Roca. You need to be careful when making such a comparison, the differences are likely to lead to an incorrect comparison. More information about these differences can be found in the section Census-to-Census Observations ... (see below).
Housing Units ...
At the time of the 2010 Census, Roca had 83 Housing Units<3> and with its population of 220 people, this averages 2.65 people per Housing Unit.
The 2010 Census shows Roca had a land area of 0.14 square miles [0.4 km²]. This translates to 597 Housing Units per square mile [230.6 housing units/km²].
From the Census of 2000: Roca had 86 Housing Units, a population of 220 people and a land area of 0.14 square miles [0.4 km²]. This gives a density of 2.56 people per Housing Unit and 617 Housing Units per square mile [238.5 housing units/km²].
NOTE: Repeating the caution above (under Population Density), be aware that when comparing Housing Units between the 2000 and the 2010 Census, there were changes in the sampling area for Roca and you need to be careful when comparing results between the censuses. More information about the changes can be found in the section called Census-to-Census Observations ... (see below).
Lancaster County ...
The community of Roca is located in Lancaster County.
The county had a population of 285,407 people at the 2010 Census. With it's population of 220 people, Roca represented 0.08% of the county's total.
In addition, where the village of Roca has a population density of 1,582 people per square mile [611 people/km²], Lancaster County averages 340.8 people per square mile [131.6 people/km²].
For more information, please visit our Census Page for Lancaster County.
Population Rings for Roca ...
To help identify the number of people who live in Roca and the surrounding area, we have drawn concentric rings centered on Roca. We counted the number of communities within each ring and summed their populations.<4>
Census-to-Census Observations ...
When the Census Bureau takes a census count (or enumeration) for Roca, they start by specifying the boundaries of the area to be counted. This area (or sampling area) is a polygon and its shape can be quite complex - it may or may not match the geographical boundaries of Roca. It's important to note that from one Census to the next, the shape and location of the polygon can change. If you need precision or details about the methodology of the Census, you should visit the U.S. Census Bureau for a definitive answer.
There is only a very minor difference in the sampling area given between the 2010 Census and the 2000 Census.
The 2010 Census shows that the total area for Roca was 0.14 square miles [0.4 km²]. Of this total, only a minor amount of the area is covered by water.
The 2000 Census shows a total area of 0.14 square miles [0.4 km²]. Of this total, only a minor amount of the area is covered by water.
While generally coinciding with the GPS location (latitude/longitude) of Roca, the latitude and longitude given by the Census Bureau actually indicates the GPS location of the polygon for Roca.
For the 2010 Census, the location was given as:
Lat: 40.658465° (or 40°39'30" N) [Map]
For the 2000 Census, the location given was:
Lat: 40.657101° (or 40°39'25" N) [Map]
The difference indicates that the U.S. Census Bureau moved the location of the polygon for the 2010 Census 542 feet to the northwest<5> of the location that was used in the 2000 Census.
The U.S. Geological Survey (USGS) and the U.S. Board on Geographic Names (BGN) have assigned a unique GNIS identifier (#2399098) to Roca. This identifier also marks a GSP point on the map, and that point lies within the boundaries of Roca. The GNIS point has been mapped to the latitude/longitude:
Lat: 40.658455° (or 40°39'30" N) [Map]
The GSP location given for the 2010 Census lies 9.57 feet to the northeast<6> of the point given by the GNIS for Roca. For more information about this and the relationship of the various Federal Codes, please visit our Misc Page for Roca.
Miscellaneous Information for Roca ...
The Federal government has assigned various identifying codes to each community, county and state. At one time or another, the US Census Bureau has used one (or more) of the following identifiers when referring to either Lancaster County or the village of Roca:
The GNIS Codes ...
The current system of identification is called the Geographic Names Information System (GNIS). The following GNIS codes relate to Roca:
GNIS ID for Roca: 2399098
The FIPS Codes ...
An earlier (and largely obsolete) identification method was called the Federal Information Processing Standard (FIPS):
State Code: 31 (Nebraska)
County Code: 109 (Lancaster County)
Place Code: 41830 (Roca)
Misc. Census Codes ...
Roca is located in Census Region #2 (the Midwest Region) and Division #4 (the West North-Central Division).
For more information about the various Federal identification codes, please visit our Misc Page for Roca.
Other Roadside Stops ...
Off-the-Road Links ...
The official website of the U.S. Census Bureau
Unfortunately, we don't know of a website for Roca. If you can help, please contact us through our Feedback Page.
The official website for Lancaster County: www.lancaster.ne.gov/
The official website for State of Nebraska: www.nebraska.gov/
The official website of the U.S. Board on Geographic Names (BGN)
The official website of the U.S. Geological Survey (USGS)
Please keep in mind that we can not guarantee the accuracy or timeliness of the information on this website, so use with care. We encourage you to double-check the information that is critical to you.
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This page was last modified: 11 Mar 2019