Baud Rate at 19200 limitations

For a special project, we consider to stream telemetry data and control via satellite communication. (Latency about 1.2 seconds) Because of the high costs per Megabyte data, it would be better to have a lower Baud Rate.
A.Will 19.200 work out?
B.Is there a way to calculate the data amount in Megabyte per hour using a Baud Rate of 19.200?

Lowering the baud rate won’t lower the data sent. You can get the GCS to ask for lower frequency updates.

cool, thank you! where can I find this parameter and any idea how to estimate the data volume per hour?