Graphing Cumulative Contribution Progress as a % of Fiscal Year Goal

Hi folks,

I'm new to my organization and new to Tessitura. I'm trying to create a graph of this year's fiscal progress as cumulative contributions. I have added a hard coded goal line of ~$4.5M, and I would like the Y axis on the right side to be expressed as a percentage of that goal, with $4.5M being 100%.

I thought I could duplicate the summed giving line and change the formula to divide it by the hardkeyed goal amount of $4.5M (RSUM([Amount])/4482522))), display it on the right side, and then see the progress to goal but it's not scaled to that goal amount line. (It should be 100% at the line, and right now it's 60%).

Has anyone tried expressing these two parameters together against a goal?

Thank you!