Read a Public Data Table by Row and Column
Use headers, units, periods, and notes to compare table entries accurately.
Start with the table title and headers
Read the title and any subtitle before scanning values. The title may identify a location, population, program, or reporting period. Column headings explain what each vertical set of values represents, while row labels identify categories or groups. Together they define the comparison the table supports.
For example, a hypothetical table could list service areas in rows and “applications received” and “applications completed” in columns. A value in the second column should not be described as the number of people served. Read the row label and column label together before interpreting a cell.
Check units and period
Find whether values represent people, households, dollars, percentages, or another unit. A footnote may say dollar values are in thousands or that percentages use eligible applicants as the denominator. Check the date range too: “2025” might mean a calendar year, fiscal year, or year-end snapshot.
Suppose a table shows $2.4 under a heading that says “amounts in millions.” The value represents $2.4 million, not $2.40. If a column is labeled “rate,” locate the denominator or definition so you know what the percentage measures.
Read notes and blank cells
Notes beneath a table can explain exclusions, revised values, abbreviations, and data limitations. A dash, blank, or zero may have distinct meanings: not applicable, unavailable, suppressed, or no recorded cases. Never treat all missing-looking cells as zero unless the source defines them that way.
If the table says one service area began reporting midway through the year, its annual figure may not be comparable with a full-year figure elsewhere. Record the caveat alongside the value. When a note refers to a symbol or letter in a cell, follow it before calculating totals or comparisons.
Make comparisons that fit the table
Choose entries with matching definitions, units, and periods. If one row reports households and another reports individuals, they are not directly comparable. If periods differ, state that difference or find a consistent period before drawing a conclusion. Use arithmetic only when the table’s categories can properly be combined.
A clear summary might say, “Area A recorded 120 completed applications and Area B recorded 95 in the same quarter.” It should not claim that Area A had more eligible residents unless the table measures eligibility. Save the table title and source with your notes so readers can check the context.
Spotted something we should look at? Suggest a correction.