Continuing its upward rally, the world's most popular digital currency, Bitcoin, touched another record high of $28, on Wednesday, recording a per cent surge from its previous high. The cryptocurrency has surged nearly half in just 15 days since it achieved the psychological milestone of $20, on December The main reason for the rising Bitcoin streak may be bulk buying by big US investors. They expect to make quick gains amid some positive developments around the cryptocurrency, including speculations that it could become a mainstream payment method.

Bitcoin has seen an unprecedented rise this year, with its value witnessing a per cent jump in , giving investors better returns than other traditional mainstream investment platforms.

Since its meteoric rise in December, Bitcoin's market value has now exceeded $ billion, as per Coindesk, a cryptocurrency platform. This is more than $ billion m-cap of Visa, the world's biggest financial service company, as per the Companiesmarketcap data. Both, however, are different and may not be compared: Visa is for-profit financial business while Bitcoin peer-to-peer software system.

Not only Visa, but Bitcoin is valued more than biggest publicly traded companies like Samsung ($ billion) and Walmart ($ billion), the data shows.

Also read:Bitcoin sprints over $27, mark; rises over $2, in 2 days

A major jump in Bitcoin price -- from $5, to $25, -- was seen after PayPal - the online payment major - announced in March that it'll enable its account holders to use Bitcoin. This marks a colossal per cent increase in the past eight months. ZebPay, one of India's largest cryptocurrency exchanges, has predicted that Bitcoin's value could hit over $, by

Meanwhile, as the popularity of Bitcoin grows, the Indian government is planning to impose 18 per cent GST on its transactions. The Central Economic Intelligence Bureau (CEIB), an arm of the union finance ministry, has put forward a proposal to impose 18 per cent GST, saying it could potentially gain Rs 7, crore annually on bitcoin trading. The CEIB came to the conclusion based on a study on levying GST on cryptocurrencies.

Also read: Bitcoin hits $25,mark; % increase since March