See for each task, which days I have worked on it or not
 

In a project, we are working in parallel in 10 different tasks. We are two people so each day we work in no more than 3 tasks. The tasks we work in every day does not depend on us. I would like to track progress in some way so that I can see visually for each task, which days I have worked in this or not. Obviously one could use the "progress" metric and update it, but then it is not clear for me the days we worked in that task.