Purchased shares = 680 shares * $11.00 ($7,480)
Year-end shares worth = 680 shares * $2.20 ($1,496)
Loss of shares = $7,480 - $1,496 ($5,984)
OR
Loss in shares price= $11.00 - $2.20 ($8.80)
Loss of shares = 680 shares * $8.80 ($5,984)
Barney can deduct $5,984 as the amount of loss of this year.