How many years of data should be analyzed for an effective GIS report?

For an effective GIS (Geographic Information System) report, analyzing data over a longer period, such as three to five years, is generally recommended rather than just one year. This is because a longer timeframe allows for more comprehensive trend analysis, helps identify recurring patterns, and accounts for seasonal variations and anomalies that might occur within a single year.

By reviewing data over several years, urban planners and emergency responders can gain deeper insights into how incidents and responses change over time, enabling them to better allocate resources, improve response strategies, and anticipate future needs. Furthermore, GIS analysis often informs policy decisions that benefit from a broader temporal context, which a single year's worth of data may not sufficiently provide. In summary, while one year of data may offer a snapshot, longer periods yield a fuller understanding, making it less effective for thorough reporting and strategic planning.