Xiao Zhang spent 5,000 yuan to buy a stock in 1996, which can increase in value every year (1/5). If Xiao Zhang has been holding this kind of stock, the total value of these stocks will exceed 10,000 yuan in how many years at the earliest.
小张1996年花5000元购得一种股票，这种股票每年可增值(1/5)．如果小张一直持有这种股票，最早在多少年这些股票得总价值会超过10000元．
<result>2_000</result>