Thomas Lee, co-founder of Fundstrat, says based on his expert opinion the decline in cryptocurrencies will let up after tax day April 17, 2018.

Lee says based on his current estimates, households in the U.S. will likely owe about $25 billion in capital gains tax for all of their cryptocurrency holdings. What we’re seeing is likely a massive sell off on cryptocurrencies before the April 17th deadline. “Buy the dip and HODL,” he recently said in a CNBC interview.

“Market timing is generally discouraged in traditional equity investing,” Lee, the former chief equity strategist at JPMorgan Chase & Co., wrote in a recent Fundstrat note. “If an investor missed out on the 10 best days (for S&P 500) each year, the annualized return drops to 5.4 percent (ex-10 best), from 9.2 percent. In other words, the case for buy and hold in equities is the opportunity cost of missing out on the 10 best days.”

Lee also noted that there has been a lot of selling pressure by cryptocurrency exchanges who are obligated to income tax in the U.S. and its territories. Cryptocurrency exchanges made incredible profits in November and December of 2017, some as high as 1 billion U.S. dollars.