Year 2015, 1USD is around 130LKR
Now 2021, 1USD us around 190LKR
With the time rupee depreciate by huge amount.
The worst scenario which is applicable for share market.
Ex. Assume, A foreign investor invest for a long time period and year 2010 he brought $1000 (1000*110=110000LKR) to invest in share market.
He analyzed that "X" company is best to invest, "X" company 1 share price in 2010 was 100LKR.
He was able to buy 1100 shares from "X" company.
After 11 years(2021) he check "X" company price and he noted that it's 160LKR.
When he sold that shares in 2021 he got (1100 shares*160)= 176,000LKR. He was happy
But, when he try to convert to his currency it was only (176000/190) = $926.
Even company make profit by 60 % during last 11 years .He has loose $(1000-926)=$74 by investing in srilankan market.
Because of this investors are hesitate to invest for long and traders will come and gain profit within short term of period.