These are the data i have from this I need to find out the current rating and previous rating I have scenarios where I will have many no.of AppraisalDates(AppraisalfromtDate,AppraisaltoDate) and I want to calculate if an employee starts the appraisal date from April(4/30/2016) to March(3/30/2017) i want show first 6 month as previous rating and next 6 months as current rating
And also I want to show the Start and End Months in chart like 'Jan to June'