Helps us to see how data are changing during some time period. For practical reason we measure trends over month, quarter, year and/ or their combination.
Trends help us to understand historical data and make forecasts based on them.

Basic trends we can see in data:

  • values are moving up
  • values are moving down
  • values are stable (in some small interval)
  • values are erratic (volatile)

Attention – difference between stable and volatile values can be sometimes unclear.
Everything depends on “interval of instability” use use and in praxis also on scale you use for charts.
If you create chart with some “on detail pointed scale” you can make very stable values look very erratic.
And vice versa.

Basic indicator we can use is trendline in chart.