No. Your retirement stipend in a Vanguard account is not virtual currency.
Virtual currency is also known as cryptocurrency. Cryptocurrency is not in US Dollars, it is its own currency. Your retirement stipend was likely issued in US dollars, even though it was transacted electronically.
For more information, see How is cryptocurrency like Bitcoin taxed?
[Edited 4/13/2020 | 11:55 PM PST]
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