How do I filter my data points without using signal processing toolbox?

I have an excel file containing 2 columns of data. Time and Encoder Raw data. From there I would like to smooth out the data (with lowpass filter FIR if possible) without using signal processing toolbox like sgolay? I have tried using sgolayfilt as a test to see if it works and now I want to do without it. How do I go about this?

Thank you very much and kind regards

[Image Analyst]

Not sure what your edit was, but you still forgot to attach the Excel workbook.

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Answer 1

[Image Analyst]

Try movmean()