Help on Excel 10 graphics.

That is an interesting problem. You will need to use a 3D column chart. One axis (X, from left to right) should be the day, the next axis (depth, meaning front to back or "into" the screen) should be the time, and the 3rd axis (height) should be the glycemic reading.

The biggest problem will be orienting the chart so you can see all the readings. Taller ones in front will hide shorter ones in back but you can usually get around this with the proper rotation, although this will take some fussing. You can rotate the chart view in any direction so the proper orientation is going to depend on what your readings are like and how many in each day there are.

You would only need three axes if you treat date and time of day as separate variables. I would instead treat time as a single variable. To do this, you'll need to use your dates and times of day to calculate a single figure representing time. The method below will give you time in days since the first reading, so the graph will start at time zero:

1. Format the first column (Column A) as dates.
2. Put the dates of the readings in that column.
3. Format the second column (Column B) as times.
4. Put the time of day (using the 24 hour clock) in that column.
5. Format the third column, Column C, as numbers with two decimal places.
6. Use this formula in the first cell in Column C:
   =(A1-$A$1)+(B1-$B$1)
7. Drag the corner of the first cell down Column C until there is a value for every date/time pair.
8. Put the blood glucose readings in Column D.
9. Select Column C and Column D and insert the chart of your choice - I would suggest a 2D line.
10. There you go :)

I have attached an Excel file that uses this method to draw a graph of glucose readings against time (using made-up data!).

Hi Flores - please do feel free to send me data and I will set up a spreadsheet for you, if that would help?

Hi Flores,

I think there must be a flaw in your formula. I have inserted your data in my worksheet and get the chart below, with the horizontal axis in days, as required: