Whether it is a company increasing sales through efficient marketing, a more balanced budget through automated expense categorization, an increase in public safety through insightful reporting summaries, or just a better understanding of our fellow humans’ behavior, data can provide powerful change. With so many details of our world now being recorded in such organized ways, we are able to efficiently process large amounts of information in our quests for understanding.
For an introduction to data study, the below examples of U.S. Census Bureau data analysis have been provided. The world is full of data. This cyborg wants her fellow humans (whether partly or fully organic) to be able to process information and use it to shape the future of our world together.
Arizona Affordable Housing - An Example of Data Study
“You’ll find affordable rent in Arizona” is proudly said in an article written by Guzman in 2024. It is not surprising that an article published by rent.com, a company that benefits from more people renting, might have accidental bias in the numbers they choose to present for renting. The article mentions only mean rental prices, and only for a select number of cities in Arizona. The average rental costs stated in this article range from $1,055 to $1,466 for a 1 bedroom.
Numbers do not lie, but their context can be misleading.
If you want to rent in Arizona, but have no idea how easy it is to find a home you can afford to rent, then where would you find information you trust? If you were to look at data from the U.S. Census Bureau, there might be a larger more important story to tell about renting in Arizona than the quick average mentioned above. Looking at a collection of many numbers in many different ways can help to reduce even accidental bias. p
Census Bureau Data: Income Brackets
“Affordable” is a measure of income against the expense. The U.S. Census Bureau surveys residential addresses every 10 years. Some of the data sets available from these surveys include rental costs and household income levels. For years between surveys the bureau estimates the natural small changes that occur over time and publishes estimated data for each year. Both of the two main data sets used in this analysis are from the U.S. Census Bureau.
To understand income in Arizona, I looked at the 2023 “Income Data in the last 12 Months” data set. This would have been for the first full year prior to when the rent.com article was published stating “affordable rent in Arizona”. The majority of Arizona households, about 62%, earn less than $100,000 and around 21% earn less than $35,000. The rent.com author provided a summarized metric (average rent). I am also providing summarized numbers, though there is information at the bottom to show where you can find and then study this information yourself. Instead of an average, I picked reference points in the data (such as $100,000 annual income) and told you how many households earn less than that referenced amount.
If we can calculate that 62% earn less than $100,000/year, then that means 38% of Arizona household make more than $100,000 in income per year (100 – 62 = 38). But, there was a second metric I gave in the last paragraph too. I wrote that 21% of Arizona households earn less than $35,000. The $35,000 limit is also included in the $100,000 limit. So, 41% of Arizonans earn greater than or equal to $35,000 and less than $100,000 per year (62 – 21 = 41).
All these calculations are present in the pie chart shown here. 21% < $35K, 41% $35K – $99K, 38% > $100K. This data is per household, meaning all that live within the home combined.
This seems to be a clear way to estimate how well a household can afford a home. You are comparing household to household values. Per individual could be much more complex because the units are different. How many people in a household? The more assumptions made, the less true to reality the analysis is likely to be.
If You are Poor in Arizona, You Most Likely Cannot Afford a Home
If you are poor in Arizona, you most likely cannot afford a home.
That is a strong statement to make, but I feel confident saying this after I looked into more data. The federal poverty guidelines are used by many states in the USA to define who is or is not impoverished (poor). Arizona uses this as their guideline for the poverty line as well. The bottom 21% of Arizona earners make less than $35,000 a year. The federal poverty guidelines, as set by the U.S. Department of Health and Human Services, state that $32,150 is the poverty line for a family of 4 (less than our $35,000 limit).
Affordable housing is generally defined as rent and utilities costing no more than 30% of income. If the bottom 21% of Arizonans were all calculated at the maximum income in their range, all at $35,000 per household per year, then $875 is the total monthly affordable rent + utilities cost for the poorest 21% of Arizonans. The U.S. Census Bureau has a data source listing rental home pricing, but utilities must be added to rent costs in order to relate to that common 30% of income limit. Although it is only an average, an article by Tromler titled “The TRUE Cost of Living in Arizona” listed the average utility cost in Arizona as $440. Given the harsh summer heats regularly blasting at over 100 degrees, this doesn’t seem completely unreasonable. That would mean $435 per month for rent to be affordable (875 – 440 = 435).
There may be over 7 million people living in Arizona, but the U.S. Census Bureau’s household income data says there were an estimated around 2.8 million households in 2023, likely more now. The bottom 21% of household incomes was estimated to include 581,732 households in that 2023 data. The U.S. Census Bureau estimates there were 48,796 housing units available with a monthly rental cost of $449 or less. That would translate to only 8% of poor Arizonans can afford housing (48,796 / 581,732 = 0.08). That means 92% of the poorest 21% of Arizona households cannot afford to rent a home with utilities (100 – 8 = 92). And remember, that was taking the highest possible income for the category for everyone in that income category.
What if the utility cost seems too high? We could take another extreme for this. What if there was no electricity, no running water, no natural gas, and no utility costs included at all? Everyone in the poorest households is estimated to be sitting in the life threateningly dangerous heat in the dark without water or sanitation in this scenario. There are 227,791 rental units available for $899 per month or less according to the U.S. Census rental price data. (The data is only easily available in of $100 increments.) In a world without utilities, just a roof overhead, only 39% of the poorest Arizonan households can afford their bare shelter without any utilities (227,791 / 581,732 = 0.39).
No matter how you slice these numbers, the majority of Arizona’s lowest income earners cannot afford housing. If you are poor in Arizona, you most likely cannot afford a home.
A series of charts might help explain even better. Visuals help explain numbers.
When looking at representations of numbers made with pictures, the relative sizes are considered. How large is the size of low income households in comparison to all households in Arizona. Is it only a tiny amount? Does it seem like a lot? Here the icon I created shows rounded numbers. Some graphics will represent exact percentages from the original data. Instead of 100 percent, 21 percent, and 8 percent, I showed 100 people, 21 people, and 2 people. The last number was a rounding up of 1.7 to 2 in order to avoid having to cut off part of an icon person’s arm. The people icons in the first group of 100 and second group of 21 are displayed in evenly spaced rows with all icons the same size and starting in the same vertical position in the overall graphic to allow for easy comparison.
Graphics are meant to communicate the overall point in less 2 seconds.
A Short Lesson on Number Facts for the Thoughtful Reader
The rent.com author and I both presented facts on Arizona rents. We summarized data using common calculations instead of simply giving you the full data set and letting you draw your own conclusions (though the data sets are linked at the bottom of my article for you to play with on your own if you like).
There are many types of summary metrics you can calculate to describe data. Reporting averages (also called means) were used in the referenced rent.com article. Averages are one of the most common ways summarize and communicate data. To understand a large amount of data in a small amount of time, many researchers use metrics that summarize the many values in a data set. Some other common metrics are median (the middle value in an ordered list of values) and mode (the most commonly occurring value). There are also quartiles, which give the minimum value in a set, the maximum value in a set, the median value in a set, the value halfway between the minimum and median values, and the value halfway between the median and maximum values. An analyst can use other values as reference points and create their own calculations from those points. From my data set it was easy to calculate the percent of total households that earned less than $35,000.
A fancy statistic term, “central limit theorem”, means that we most often use metrics at the middle point in a range of numbers. An average will not tell you the smallest value in the data, the largest value, or how many values are present in different areas of the overall range. For example: an average rent of $1,000 does not tell you if the lowest rent is a minimum value of $900 or $500. That average does not tell you if the highest rent is maximum value of $1,100 or $5,000. If a data set listing available rents has a lot of small values and a lot of large values, an average would balance out in the middle of the range (maybe at $1,000) even if there are very few homes for rent at that price. In reality, a town might have two very opposite groups of housing for rent. There might be mostly small old run down pest infested homes and then a hillside of million dollar luxury homes, with very little in between. The middle class household hoping to move to that town would be very disappointed with their actual housing options if they made their decision based on reading about an average rent in that town being in their expected middle income lifestyle’s range.
The number of homes available for rent at different prices is incredibly important when looking for a home you can afford. If there is only 1 affordable home available and 100 people need a home, then it will be very difficult to succeed at renting an affordable home. It also may be a sign that housing will continue to become more and more expensive in the area. If there is less supply of homes than there is demand for homes, then landlords can increase the price for their supply and enough of the people in demand will still likely be willing to pay at the higher price.
I did many more different calculations on the U.S. Census Bureau data to analyze the data before choosing a direction to focus on. After looking at other calculations I decided that those most in need deserved to have their needs shown. In order to show that need I needed to understand it with a more in depth analysis.
Perhaps you wish to do your own analysis at a level somewhere more complex than the rent.com author’s simple rent price average, but more simple than my calculated comparisons between multiple data sources. Quartiles may be another great option to quickly understand data better rather than only calculating an average (which has it’s limits, as the central limit theorem states).
Using quartiles from the U.S. Census Bureau’s rent data set, I found that I could estimate that less than 25 percent of rental contracts were for less than $900 per month, over 50 percent of monthly rents were for amounts between $1,000 and $2,000, and the final 25 percent were in excess of $2,000. The maximum rent reported in the survey was “$3,500 or more”, which was estimated to be the monthly rental cost for over 10,965 housing units in the state.
There are many ways to look at data, many ways to summarize and compare numbers. Data analysis is about taking a large amount of information and using it to create simple understandable true stories.
This cyborg is always wanting to know more about the world, always seeking knowledge, always seeking data.
Try this U.S. Census Data Analysis Project Yourself with the References Below
Guzman, A. (October 2, 2024). Is Arizona a Good Place to Live? 10 Pros and Cons of Renting in Arizona. RentBlog. Retrieved January 11, 2025, from:
https://www.rent.com/blog/is-arizona-a-good-place-to-live/
Tromler, C. (2024). The TRUE Cost of Living in Arizona. UpNest. Retrieved January 11, 2025, from:
https://www.upnest.com/1/post/cost-of-living-arizona/#:~:text=You%20can%20expect%20to%20spend,air%20conditioning%20to%20stay%20cool.
U.S. Census Bureau, U.S. Department of Commerce. (2023). Contract Rent. American Community Survey, ACS 5-Year Estimates Detailed Tables, Table B25056. Retrieved January 11, 2025, from:
https://data.census.gov/table/ACSDT5Y2023.B25056?q=United States&t=RenterCosts&g=010XX00US_040XX00US04.
U.S. Census Bureau, U.S. Department of Commerce. (2023). Income in the Past 12 Months (in 2023 Inflation-Adjusted Dollars). American Community Survey, ACS 5-Year Estimates Subject Tables, Table S1901. Retrieved January 11, 2025, from:
https://data.census.gov/table/ACSST5Y2023.S1901?q=United States&t=Income (Households, Families, Individuals)&g=010XX00US_040XX00US04.
Office of the Assistant Secretary for Planning and Evaluation, U.S. Department of Health and Human Services. (2025). HHS Poverty Guidelines for 2025. Retrieved April 19, 2025, from:
https://aspe.hhs.gov/topics/poverty-economic-mobility/poverty-guidelines