Hello Yvette,
Yes, the one at Zack's is one-page. I have seen one-pagers up to 120-pagers. I think a good range is around 5-12 pages, with a sweet spot of around 8 pages. The reports I created were entirely embedded in Excel. My workbooks began with a summary worksheet that looked like a Zack's-type analysis. The data in that summary was pulled from the other worksheets in the workbook. So individual worksheets handled one major calculation. For example, a worksheet to calculate a GDP forecast; a financial statement analysis of annual results; a valuation; comparisons with competitors; and so forth.
Yours, in service,
Jason