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Many tables require explanatory notes. The rule is, if information is vital for understanding a table, for example spelling out abbreviations or explaining the presence of empty cells or of notes in some cells, then this should be explained above the table. The source of the data, if it is different for each worksheet, should go in a row above the table.Notes of secondary importance, for example, the status of some data, can be positioned after the table
1. The worksheet doesn't have a title. There's an empty row. The table has two heading rows so is impossible to mark up as table. Important information is left to a footnote below the table.
2. the worksheet now has a title in A1 in heading 1. Then a description of what is on this worksheet. Then the title of the table. And the important information is now pasted above the table
3. To get rid of the merged cells at the top and reduce the column headers to one row, we can add the years to the 'child' column header rows. This will allow us to mark this up as a table.
4. Having come this far, why make the reading experience more complicated with abbreviations at all? Why not spell out S, I and R in each column heading? This is a bombproof solution.
And also, finally, remove the colour.
Possible the percentage symbol could be removed and explained in a description sentence above the table, to further reduce clutter.
Footnotes
Currently, many tables include footnotes using symbols and superscript and, most often of all, asterisks. This should all be avoided. Some screen readers do not read superscript or asterisks. The partially sighted will struggle ot make out tiny numbers or letters in superscript.
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