Below is a lengthy code that I have coded on the label of the chart as attached. It gives me the Alliance computed MOM%, YOY% and YTD% with extrapolation involved. I am thinking whether is there any ways to shorten the code and more efficient in maintaining. Thanks.
Additional to the suggestion from jonathan dienst (you should do it first) - if you used some expression-varities often you could put some expression-parts into variables or you could use parametrized variables as expression, here an example: