Allow for duel axis on chart

We are looking to build one chart that can show multiple axis of data. Basically, We are needing a chart (preferably horizontal column chart) to show us actual vs expected days for particular products.

The way we capture the expected number of days is with a simple custom field that we enter that number. The actual number of days is calculated off of the start date with the formula of Today()- Field("field name"). This method does allow us to capture the information and produce two charts that show the difference. The preference would be to show the difference between the actual and expected on one chart. In other words we would like to show products as a "x" axis, let's say and then have the actual and expected shown as separate columns next to its respective product showing the difference in days.