How do I adjust a 15 month fiscal year to 12 years?

Hi all,

I am looking through financial statements from 2012-2019. Prior to 2016, the company provided their financial statements with fiscal years of 15 months. I do have access to the adjusted net sales from 2012-2016. However, how do I adjust COGS from 2012-2016?

Thank you!

Do you have the quarterly or year-to-date data for the same period? If not, the only way to approach this would be to use estimates based on the 15-month periods.

Thank you! I will do my ratio analysis based on 15 months.