Avenue Supermarts, the parent company of Indian retail chain D-Mart, listed on the bourses on March 21. It made a blockbuster debut, the best in five years at least, according to data from PRIME Database, a capital markets information provider.

D-Mart’s shares opened at Rs604.4 a piece on March 21. This is 102% higher than the stock’s offer price—the price at which shares are first sold to investors during the initial public offering (IPO)—of Rs299. Some subscribers had their investment almost double in value by the end of the opening day, a Moneycontrol analysis showed.

Sixty-nine companies have listed on stock exchanges in India since Jan. 01, 2012, and D-Mart’s gain on the day it got listed was the highest among them, data shows. The listing day gain is the percentage difference between the closing price of the stock on the first day and its offer price.

Such a performance has made D-Mart the most valuable listed retail chain in Asia’s third-largest economy. The family wealth of the company’s founder, 62-year-old stock-broking veteran Radhakishan Damani, has leapfrogged; it is higher than that of other billionaire industrialists such as Anil Ambani, Ajay Piramal, and Adi Godrej. The value of the Damani family’s stake—some 82%—in D-Mart is now worth $5 billion. Before the listing, Forbes had pegged it at $2.3 billion (as of March 20).

Damani founded D-Mart in 2002 with a single store, and it is today one of India’s most profitable retail businesses with 118 outlets. In financial year 2016, it recorded a net profit of Rs321.2 crore on revenues of Rs8,606 crore. Damani’s early business decisions like focusing on value retail and investing in real estate, have helped D-mart emerge as a star in India’s $600-billion retail market.

On March 22, a day after the debut, the stock was trading at Rs642.88 per share as of 12:51 pm on the BSE, 0.28% higher than its previous close.