ADXL372 sampling rate

Question

Hi, 
 I am confused with the number of data points I am receiving with the ADXL372. 
 I have the sensor connected to a raspberry pi through SPI, with the bandwidth set to 3200 Hz and the ODR to 6400 Hz. With the current set up I trigger the raspberry to read and store the 6 bytes of x,y,z data in a byte array whenever there is new data ready for 1 second, which i then convert to the corresponding g values. 
 The number of samples I am receiving is approximately 7150 per second. 
 I am only new to this, so wondered if this rate is valid, or if i would need to downsample to the specified ODR? The application is for quantifying head impact accelerations just FYI. 
 
 Thank you

NevadaMark · Accepted Answer

OK, after consulting with our subject matter expert, it appears like I missed a key plot in the ADXL372 datasheet, which answers this question. From this plot, I can easily imagine +/-15% variation and perhaps, even wider. 
 
 The bottom line is that I need to correct my starting position: you observation is within what we might expect. 
 I hope that this helps!)

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ADXL372 sampling rate