Hi Abe,

Yes, you can definitely draw trend lines through only certain data points in Excel. Here's how you can do it:

1. First, create a scatter plot with all of your data points included.
2. Next, select the data points that you want to include in your first trend line. You can do this by clicking on a data point and then holding down the Ctrl key while clicking on the other data points.
3. Right-click on one of the selected data points and choose "Add Trendline" from the menu.
4. In the "Format Trendline" pane that appears on the right side of the screen, choose the "Linear" option under "Trendline Options."
5. Under "Forecast," you can choose the "Forward" and "Backward" values to extend the trendline beyond your selected data points if you wish.
6. Repeat steps 2-5 for the second set of data points that you want to include in your second trend line.
7. You can customize the appearance of your trend lines by changing the color, line style, and thickness in the "Format Trendline" pane.

That's it! You should now have two trend lines on your scatter plot, each going through only the selected data points. Let me know if you have any questions or need further assistance.