On the main "Quote" page of every fund covered by Morningstar is a chart showing the growth of $10,000 over the last 10 years (for funds that are 10 years or older). In 18 days the return figure for 2009 will disappear. For many funds, especially in the technology and growth sectors, this will make an enormous difference to their headline 10 year total return.
For example, FSELX returned an astonishing 85% in 2009. Yet in the decade since it has frequently lagged its category. Its standout performance in 2009 clearly contributed massively to its 10 year total return of almost $102,000.https://www.morningstar.com/funds/xnas/fselx/quote
Personally, I'll be glad to see the figures for 2009 disappear. They have distorted the performance of many, if not most, mutual funds and ETFs. Hopefully, a more accurate picture will emerge from 2020 onward.
Wishing everyone here a very happy holiday season.