you misread the article.  This article is ONLY about estimating your cost of living in retirement.  This LSRR is meant to eliminate the wide fluctuations and outliers in peak income which used to be in the main measurement tools based on peak earnings.  Instead the LSRR looks at what specific expenses you have and eliminates all the career, monthly savings, mortgage, and kids costs from that to find a realistic cost of living tailored to your retirement.  Like me you have a business where the income changes a lot, and took a long time to get rolling then returned huge income.  But like me you probably not spend all the extra high income on hukersandblow, instead banked it. That would skew the old measure of 70% peak earnings, but it is removed from the LSRR calculations.