Line Chart filter by drop down

I'm trying to set up a graph that shows the total amount of time spent on a project each month, including all time up to that point. My data is stored in a table with columns for the project number, date and time spent. I've set up a Single Selection Page Level Filter to filter the chart to show one project at a time. 

My problem is that whenever I create a new meassure they aren't filtered by the current project. If I don't use a filter it takes the sum of all projects. I can hard code a filter for a specific project to get the right amount but I need to be able to filter dynamically by whatever project the line chart is filtered to.