I/O Type >> Analog Input >> Timing >> Maximum Multiple Channel Rate

NI-DAQmx C Properties

I/O Type >> Analog Input >> Timing >> Maximum Multiple Channel Rate

Data Type: float64
Description: Indicates the maximum rate for an analog input task if the task contains multiple channels from this device. For multiplexed devices, divide this rate by the number of channels to determine the maximum sampling rate.
Restrictions: Not Settable

You can get this property using:
  DAQmxGetDevAIMaxMultiChanRate