National and regional statistics are generalities, essentially summaries generated by thousands of unique, individual listings and sales occurring across different market segments. They are best seen not as precise measurements, but as broad, comparative indicators with reasonable margins of error. Anomalous fluctuations in statistics are not uncommon, and last period data should be considered preliminary estimates which may be revised in future updates. Different analytics programs sometimes define standard statistics - such as "active listings," "days on market," and "months supply of inventory" - differently: What is most meaningful are not specific numeric calculations but the trends they illustrate. Data from sources deemed reliable, but may contain errors, and subject to revision. All numbers to be considered approximate, and how these analyses apply to any particular property is unknown without a specific comparative market analysis.