If you select a compression type for a line type that is not a logged line, Trending:

Automatically determines the group size that the data point represents..

Applies the selected compression method (for example, average) to that group.

Plots all the data points in the group as a single data point as follows:

Select compression for a line type that does not have historical data:

1. (If the Line Display dialog box is not open) Open the Line Display dialog box.

1. Select a line in the Lines grid.

2. Click Display….

The Line Display dialog box opens.

2. Select a compression type in the Compression field to display one of the following plotted values.

Compression Type	Plotted Value
None	Multiple data points along a vertical line.
Average	The average of the values within the automatically determined group size.
First	First value in the group
Last	Last value in the group
Minimum	Minimum value in the group
Maximum	Maximum value in the group

Note: Server side compression is only available for lines with historical data.

More information

Option 5.2. Trend Line Compression or Sample Type.

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