Pearling had come to play a pivotal commercial role in Doha by the 20th century. The population increased to around 12,000 inhabitants in the first half of the 20th century due to the flourishing pearl trade. A British political resident noted that should the supply of pearls drop, Qatar would 'practically cease to exist'. In 1907, the city accommodated 350 pearling boats with a combined crew size of 6,300 men. By this time, the average prices of pearls had more than doubled since 1877. The pearl market collapsed that year, forcing Jassim Al Thani to sell the country's pearl harvest at half its value. The aftermath of the collapse resulted in the establishment of the country's first custom house in Doha.