I think part of the issue is is that the amount of shares that Grayscale sell is so small that it doesn't necessarily show up on the 1099B, resulting in the "Quantity" being listed as 0.000
What I set up tonight was a sheet that takes the product of, the closing price of GBTC on the respective date, the Cost Basis Factor on the respective date, and the number of shares I held on that date.
So for example this would result in something that looks like this for 1/8/2021:
(Closing price that date)*(Cost Basis Factor that date)*(Number of Shares)=Cost Basis
$44.42*0.[removed]*100 shares=~$1.68
Whereas the amount on the 1099B would be $1.42.
So I feel like in this case for the blanks in 1b I would put whatever day I purchased this stock, and in 1e I would put $1.68. The sales category would depend on the purchase date compared to the date that Grayscale sold the stock.
I am firmly not a tax expert however and it would be great to have someone else weigh in on this.
