Write the question first
Recent direction, change since purchase and change across a market cycle are different questions. Record which one matters before calculating the answer.
Hold the calendar month constant
Same-month comparisons reduce seasonal mismatch. If the series is seasonally adjusted, state that too. Avoid comparing a spring peak with a winter trough without an explicit reason.
Show a second horizon when direction changes
If one baseline produces an increase and another a decline, report both and explain what each interval contains. That disagreement is useful information, not an error to hide.
Keep the metric definition fixed
Do not switch between modeled values, asking prices and sale prices to create a continuous story. Name the provider, geography, segment and metric every time.
Do not turn history into a forecast
A past increase or decline does not establish the next move or the value of a property. Use current property evidence and the household’s actual decision constraints.
Sources & further reading
- Zillow Housing Data and metric definitions checked 2026-09-29
Your next chapter
Let’s make it
a good move.
Bring your questions. Start a conversation with Gary’s team.