Real Estate Market Analysis: Transactions, Inventory, and Price Indices

Real estate numbers move markets, mortgages, and mood. Before you trust one, know what it measures and what it leaves out.

Market Survey Analysis view: This guide is built for the decision of whether a housing or commercial real estate reading is strong enough to guide a purchase, a pricing call, or a development timeline. Start with the boundary, then test the evidence chain. For related market intelligence and research workflows, keep the definition, source and decision in one review record.

How to read the result

Every real estate figure sits inside four layers: the geography it covers, the property type it counts, the time window it reports, and the method used to turn raw transactions into a single number. Miss one layer and the headline can mislead even when the arithmetic is correct.

Headlines travel faster than footnotes. A national median price figure gets quoted in a local pitch deck. A single metro's inventory shortage becomes a claim about the whole country. The number did not change on its trip from report to conversation, but its meaning did. Reading the result well means asking what it covered before asking what it says.

Existing home sales vs new construction

Existing home sales and new construction sales are counted differently and behave differently. Existing sales are recorded at closing, months after the buyer and seller agreed on price. New construction sales are often recorded at contract signing, well before the home is finished. A gap between the two series is not always a market signal. Sometimes it is a timing artifact built into how each series is measured.

Decision check: if a claim compares "home sales" without stating existing or new, treat it as incomplete. Ask which series, ask the recording point, and ask whether the two were blended into one number that hides the split.

Inventory and months of supply

Inventory counts active listings at a point in time. Months of supply divides that count by the recent pace of sales, giving a rough answer to "how long would it take to sell everything on the market at the current rate." The math is simple, but the inputs move independently. A rise in months of supply can mean more listings, fewer sales, or both at once, and each cause points to a different market story.

Decision check: do not read a single months of supply figure without checking whether the change came from the numerator or the denominator. A market with rising inventory and steady sales is different from one with falling sales and flat inventory, even if both produce the same headline number.

Price index methodology: repeat-sales vs median price

Two houses can sell in the same neighborhood for very different prices because they are different houses. A median price index just tracks the middle value of whatever sold that month, so it moves when the mix of homes changes, not only when true prices change. A repeat-sales index instead tracks the same properties across multiple sales over time, which controls for the mix problem but requires enough repeat transactions to be reliable.

Decision check: before comparing price indices across sources, confirm both use the same method. A median price index and a repeat-sales index can tell opposite stories in the same month for the same city, and neither one is wrong. They are answering different questions.

This is the same discipline covered in our piece on turning geography into a decision: a number is only comparable to another number built the same way.

Mortgage rate transmission

A change in the benchmark rate does not reach every buyer at the same speed. Rate transmission depends on how many buyers are shopping for a new loan versus refinancing, how lenders price risk in that specific market, and how much of the buyer pool pays in cash. A market with a high share of cash buyers will show weaker rate sensitivity than one where most purchases depend on financing.

Decision check: when a report links a sales slowdown directly to a rate move, look for the cash buyer share and the average time on market. Without those two figures, the rate story is a plausible guess, not a demonstrated cause.

Vacancy and absorption for commercial real estate

Commercial vacancy rates measure unoccupied space as a share of total inventory, but they say nothing about direction on their own. Absorption, the net change in occupied space over a period, tells you whether the market is filling up or emptying out. A market can carry a high vacancy rate and still show positive absorption, meaning it is improving from a weak starting point.

Decision check: pair vacancy with absorption before drawing a conclusion about a commercial submarket. A vacancy rate on its own is a snapshot. Absorption is the trend line, and the trend line is usually the more useful number for a leasing or investment decision.

Permit-to-completion pipeline timing

Building permits are issued long before ground is broken, and completions are recorded long after that. The gap between permit and completion varies by property type, local approval speed, and labor and material availability. Reading permit data as a forecast of near-term supply without adjusting for that lag overstates how fast new inventory will actually reach the market.

Decision check: match the pipeline stage to the decision horizon. Permits inform a two to three year supply view. Units under construction inform a shorter view. Completions describe the past, not the future.

A practical evidence table

A table like this is a control device, not a decoration. It forces the same four questions onto every metric before it earns a place in a report: what does it measure, where did it come from, and what can it not tell you. Our note on using secondary data without losing market context covers the same discipline applied to numbers you did not collect yourself.

What this analysis does not prove

None of these metrics, alone or combined, prove that a specific property or submarket will outperform another. They describe aggregate conditions across a defined geography and time window. A single asset can move against the trend for reasons the aggregate data will never capture, including condition, location within the submarket, and the specific terms of a deal.

These metrics also do not establish causation between rate moves, policy changes, and price outcomes. They show correlation over a period. Treating a correlation as a guarantee is the most common way a sound real estate analysis gets stretched past what it can support.

Review checklist before publication

• Confirm whether sales figures separate existing homes from new construction, or state clearly if blended
• Check whether an inventory change came from listings, sales pace, or both
• Identify the price index method used and avoid comparing repeat-sales figures to median price figures directly
• Note the cash buyer share when a report attributes a slowdown to mortgage rates
• Pair any vacancy rate with an absorption figure before drawing a trend conclusion
• Match permit, construction, and completion data to the correct decision horizon

Frequently asked questions

What is the difference between existing home sales and new construction sales?

Existing home sales are recorded at closing. New construction sales are often recorded at contract signing, months before the home is finished. Comparing the two without noting this timing gap can overstate or understate real market movement.

Why do months of supply figures sometimes look misleading?

Months of supply is a ratio of listings to sales pace. It can rise because listings increased, because sales slowed, or both. The headline number does not tell you which, so the underlying cause needs a separate check.

Is a repeat-sales price index better than a median price index?

Neither is universally better. A repeat-sales index controls for changes in the mix of homes sold, which a median price index does not. The right choice depends on the question being asked and the depth of transaction history available.

How much do mortgage rates actually affect home sales?

It depends heavily on the share of buyers relying on financing versus paying cash, and on how quickly local lenders reprice risk. The same rate move can affect two markets very differently.

Why does a high commercial vacancy rate not always mean a weak market?

A high vacancy rate paired with positive absorption shows a market that is filling up from a weak base. The rate alone is a snapshot. Absorption shows the direction of travel, which usually matters more for a decision.

Sources and method notes

The metrics and methods above are described at a general level. For current figures and full methodology detail, consult the primary sources directly rather than relying on secondhand summaries. See our broader library at Market Survey Analysis for related research method guides.

• National Association of Realtors Housing Statistics. Existing-home sales, inventory and price data for the United States housing market. Checked on 2026-09-19.
• U.S. Census Bureau Annual Business Survey. Business and establishment-level survey methodology and coverage. Checked on 2026-09-19.
• Office for National Statistics Methodology. Official-statistics production, quality, concepts and methodological practice. Checked on 2026-09-19.

Next step

Use this framework to define a focused brief, test the evidence and identify the next decision. If the boundary or source base needs work, request a custom research discussion rather than forcing a weak number into a plan.