Calculating Annual ROI

Hi. I was wondering if anyone could put together a simple spreadsheet that would replicate the Annual ROI result of 47.66% in the attached report. The spreadsheet I put together (also attached) is coming up with an annual ROI figure of 47.71%. No matter how I manipulate the decimal points and rounding, I can't seem to arrive at 47.66%. It could be that the report is wrong and my spreadsheet is correct, but I doubt it.

Thanks,
Scott