Oakmark Funds performance statistics are updated at the end of each month to indicate performance for the previous 3 months as well as year-to-date performance, according to Oakmark Fund's official website. The statistics are current as of the last day of the previous month.
Oakmark Funds lists average total returns on its website with tickers for specific ranges, including 3-month, year-to-date and 1-year, 3-year, 5-year and 10-year averages for each of the stocks in its fund, according to the company's website. It also shows the average annual total returns since the fund's inception and the inception date for each stock. In addition, the expense ratio for the individual stocks in the fund is displayed.