I want to set up a calendar of activities down to day level. I would like to
format a cell background to a color indicating that an activity needs to
occur that day and then insert a checkmark when complete. Then I would like
to create a formula cell that checks the planned (i.e. cells where background
is a color) versus whether complete or not for a period of time (across 7
cells, and a month of cells).

I'm open to various options, but thought that setting colors and then check
contents would work. Any ideas on how to accomplish?

Thanks in advance!
--
Steve