What do you do when you have a gap in your data?


Question:  What happens if a particular measure has not been collected for a period, for example a couple of weeks? Would you simply not enter data in the graph, or is there a way to elegantly mention that the data is missing for that period? Do you have a tip?

Whenever you don’t have data for a measure you’re reporting regulary, I would simply provide a comment along with the chart (up to date with the latest data that was available) that says the data is missing, or is late.

If the data is late, that’s fine because you can state when the data will be available again e.g. “This measure will next be updated in May 2011.”

If the data is missing because it wasn’t collected for whatever reason and you will effectively have a month or two of no data, but then will pick up the data collection again, leave the gaps in the measure’s line in the chart, to show visually that data is missing. Also explain this with a comment in the report, and perhaps even a small annotation on the chart near the missing points.

It’s just as important to make clear the integrity of the data, as it is to make clear the signals.