Toll revenues for Egypt's Suez Canal have fallen in September, dampening hopes that a new parallel waterway — which authorities claim will boost the economy — can do much for it in the immediate future.

Data released on Monday by canal authorities shows that monthly revenue fell to $448.8 million, putting the year-to-date toll income at $3.9 million. That compares to a monthly figure of $469.8 million in September of last year, when year-to-date toll income stood at $4.1 billion.

The canal's much-hyped extension was one of the mega-projects President Abdel-Fattah el-Sissi said would bring an economic turnaround to the country.

But economists and shippers have questioned the project's value, saying the increased traffic and revenues the government is hoping for would require major yet unanticipated growth in global trade.