Grayscale Bitcoin Investment Trust, or GBTC, which tracks Bitcoin’s ($BTC) market price, has seen its net asset value hit its lowest point since the cryptocurrency’s price surged late last year. Shares of GBTC are down around 80 percent since bitcoin hit a high of $19,511 in mid-December. Some investors correlate GBTC’s downward trend with its expense fees, which is $20 for every $1,000 invested, or 2 percent. For comparison, the average equity mutual fund expense ratio was around 0.59 percent in 2017.