I'm trying to understand how year-over-year and YTD performance values are calculated. I thought it was obvious and straightforward, but I can't replicate the values my bank shows for even a simple example.
I looked at the performance of SPY and tried to perform the calculation myself. My bank provided the following data for SPY on Jan 1 of each year since 2020 (manually typed, did my best to avoid an error):
I'm not sure if I should be using the open, low, high, or close numbers, so I calculated the YoY percent gain as 100*(value at end of year - value at start of year)/value at start of year.
Comparing this to the Calendar year % returns reported by my bank, none of the numbers are even close:
|Date||YoY % (Market Value)||YoY % (NAV)|
What am I doing wrong?