Expert Community. I am trying to figure out how to write an expression in the Reference Line area where I can adjust a reference line from one value to another mid year. My example is a simple bar chart. I have a bar chart with 13 months (e.g. Nov 14 to Nov 15) where each bar references a value. I have a goal line set at let's say 65%. Beginning halfway through the year the goal line has been adjusted to let's say 75%. How do I write an expression showing the goal line moving from 65% for the first 6 months and then going to the new limit for the remaining 7 months?